diff --git a/projects/request/src/lib/request.service.ts b/projects/request/src/lib/request.service.ts
index 41e26cd5a..7e3d56e97 100644
--- a/projects/request/src/lib/request.service.ts
+++ b/projects/request/src/lib/request.service.ts
@@ -14,6 +14,7 @@ import { has, isEmpty, each } from 'lodash';
 interface RequestOptions {
   headers?: any;
   params?: any;
+  observe?: string;
 }
 
 @Injectable({ providedIn: 'root' })
@@ -127,6 +128,9 @@ export class RequestService {
     if (!has(httpOptions, 'params')) {
       httpOptions.params = '';
     }
+    if (!has(httpOptions, 'observe')) {
+      httpOptions.observe = 'body';
+    }
 
     const request = this.http.get<any>(this.getEndpointUrl(endPoint), {
       headers: this.appendHeaders(httpOptions.headers),
diff --git a/projects/v3/src/app/components/activity/activity.component.ts b/projects/v3/src/app/components/activity/activity.component.ts
index 484dbbccb..7e61561ff 100644
--- a/projects/v3/src/app/components/activity/activity.component.ts
+++ b/projects/v3/src/app/components/activity/activity.component.ts
@@ -1,4 +1,5 @@
-import { Component, EventEmitter, Input, OnChanges, OnInit, Output, SimpleChanges } from '@angular/core';
+import { Subject } from 'rxjs';
+import { Component, EventEmitter, Input, OnChanges, OnDestroy, OnInit, Output, SimpleChanges } from '@angular/core';
 import { SharedService } from '@v3/app/services/shared.service';
 import { UnlockIndicatorService } from '@v3/app/services/unlock-indicator.service';
 import { Activity, ActivityService, Task } from '@v3/services/activity.service';
@@ -6,13 +7,14 @@ import { Submission } from '@v3/services/assessment.service';
 import { NotificationsService } from '@v3/services/notifications.service';
 import { BrowserStorageService } from '@v3/services/storage.service';
 import { UtilsService } from '@v3/services/utils.service';
+import { takeUntil } from 'rxjs/operators';
 
 @Component({
   selector: 'app-activity',
   templateUrl: './activity.component.html',
   styleUrls: ['./activity.component.scss'],
 })
-export class ActivityComponent implements OnInit, OnChanges {
+export class ActivityComponent implements OnInit, OnChanges, OnDestroy {
   @Input() activity: Activity;
   @Input() currentTask: Task;
   @Input() submission: Submission;
@@ -25,6 +27,7 @@ export class ActivityComponent implements OnInit, OnChanges {
   // false: at least one non-team task
   @Output() cannotAccessTeamActivity = new EventEmitter();
   isForTeamOnly: boolean = false;
+  private unsubscribe$: Subject<any> = new Subject();
 
   constructor(
     private utils: UtilsService,
@@ -32,17 +35,28 @@ export class ActivityComponent implements OnInit, OnChanges {
     private notificationsService: NotificationsService,
     private sharedService: SharedService,
     private activityService: ActivityService,
-    private unlockIndicatorService: UnlockIndicatorService,
+    private unlockIndicatorService: UnlockIndicatorService
   ) {}
 
-  ngOnInit() {
-    this.leadImage = this.storageService.getUser().programImage;
-    this.unlockIndicatorService.unlockedTasks$.subscribe((unlockedTasks) => {
-      this.newTasks = {};
-      unlockedTasks.forEach((task) => {
+  ngOnDestroy(): void {
+    this.unsubscribe$.next();
+    this.unsubscribe$.complete();
+  }
+
+  resetTaskIndicator(unlockedTasks) {
+    this.newTasks = {};
+    unlockedTasks
+      .filter((task) => task.taskId)
+      .forEach((task) => {
         this.newTasks[task.taskId] = true;
       });
-    });
+  }
+
+  ngOnInit() {
+    this.leadImage = this.storageService.getUser().programImage;
+    this.unlockIndicatorService.unlockedTasks$
+      .pipe(takeUntil(this.unsubscribe$))
+      .subscribe(this.resetTaskIndicator);
   }
 
   ngOnChanges(changes: SimpleChanges): void {
@@ -56,23 +70,28 @@ export class ActivityComponent implements OnInit, OnChanges {
 
       const currentValue = changes.activity.currentValue;
       if (currentValue.tasks?.length > 0) {
-        this.activityService.nonTeamActivity(changes.activity.currentValue?.tasks).then((nonTeamActivity) => {
-          this.isForTeamOnly = !nonTeamActivity;
-          this.cannotAccessTeamActivity.emit(this.isForTeamOnly);
-        });
+        this.activityService
+          .nonTeamActivity(changes.activity.currentValue?.tasks)
+          .then((nonTeamActivity) => {
+            this.isForTeamOnly = !nonTeamActivity;
+            this.cannotAccessTeamActivity.emit(this.isForTeamOnly);
+          });
 
         const unlockedTasks = this.unlockIndicatorService.getTasksByActivity(this.activity);
+        this.resetTaskIndicator(unlockedTasks);
         if (unlockedTasks.length === 0) {
           const clearedActivities = this.unlockIndicatorService.clearActivity(this.activity.id);
           clearedActivities.forEach((activity) => {
-            this.notificationsService.markTodoItemAsDone(activity).subscribe();
+            this.notificationsService
+              .markTodoItemAsDone(activity)
+              .pipe(takeUntil(this.unsubscribe$))
+              .subscribe();
           });
         }
       }
     }
   }
 
-
   /**
    * Task icon type
    *
diff --git a/projects/v3/src/app/components/assessment/assessment.component.ts b/projects/v3/src/app/components/assessment/assessment.component.ts
index 09464ea65..dfe5b36c9 100644
--- a/projects/v3/src/app/components/assessment/assessment.component.ts
+++ b/projects/v3/src/app/components/assessment/assessment.component.ts
@@ -127,7 +127,7 @@ export class AssessmentComponent implements OnInit, OnChanges, OnDestroy {
       }),
     ).subscribe(
       (data: {
-        autoSave: boolean;
+        autoSave: boolean; // true: this request is for autosave; false: request is for submission (manual submission);
         goBack: boolean;
         questionSave?: {
           submissionId: number;
@@ -297,7 +297,6 @@ export class AssessmentComponent implements OnInit, OnChanges, OnDestroy {
       this.doAssessment = true;
       if (this.submission) {
         this.savingMessage$.next($localize `Last saved ${this.utils.timeFormatter(this.submission.modified)}`);
-        this.btnDisabled$.next(false);
       }
       return;
     }
@@ -637,6 +636,10 @@ export class AssessmentComponent implements OnInit, OnChanges, OnDestroy {
     return this.utils.isColor('red', this.storage.getUser().colors?.primary);
   }
 
+  /**
+   * Resubmit the assessment submission
+   * (mostly for regenerate AI feedback)
+   */
   resubmit(): Subscription {
     if (!this.assessment?.id || !this.submission?.id || !this.activityId) {
       return;
diff --git a/projects/v3/src/app/components/multi-team-member-selector/multi-team-member-selector.component.html b/projects/v3/src/app/components/multi-team-member-selector/multi-team-member-selector.component.html
index 1695b0279..b1039ad18 100644
--- a/projects/v3/src/app/components/multi-team-member-selector/multi-team-member-selector.component.html
+++ b/projects/v3/src/app/components/multi-team-member-selector/multi-team-member-selector.component.html
@@ -11,7 +11,7 @@ <h3 class="for-accessibility" [id]="'multi-team-member-selector-question-' + que
       </ion-item>
     </ng-container>
   </ion-list>
-  
+
   <ng-container *ngIf="review?.comment">
     <ion-item class="feedback-title ion-no-padding" lines="none">
       <ion-icon class="ion-padding-horizontal" name="eye" size="small"></ion-icon>
@@ -57,13 +57,13 @@ <h3 class="for-accessibility" [id]="'multi-team-member-selector-question-' + que
       [ngClass]="{'item-bottom-border': i !== question.teamMembers.length - 1 }">
       <ion-label class="white-space-normal body-2 black">
         {{ teamMember.userName }}
-        <p *ngIf="submission.answer.includes(teamMember.key)">
+        <p *ngIf="submission?.answer?.includes(teamMember.key)">
           <ion-chip class="label orange" i18n>Learner's answer</ion-chip>
         </p>
       </ion-label>
       <ion-checkbox color="success"
         [attr.aria-label]="teamMember.userName"
-        [checked]="review.answer ? review.answer.includes(teamMember.key) : false"
+        [checked]="review?.answer?.includes(teamMember.key)"
         [value]="teamMember.key"
         slot="start"
         (ionChange)="onChange(teamMember.key, 'answer')"
diff --git a/projects/v3/src/app/pages/activity-desktop/activity-desktop.page.ts b/projects/v3/src/app/pages/activity-desktop/activity-desktop.page.ts
index 7ea3220e8..8c05a95a1 100644
--- a/projects/v3/src/app/pages/activity-desktop/activity-desktop.page.ts
+++ b/projects/v3/src/app/pages/activity-desktop/activity-desktop.page.ts
@@ -1,3 +1,4 @@
+import { UnlockIndicatorService } from './../../services/unlock-indicator.service';
 import { DOCUMENT } from '@angular/common';
 import { Component, Inject, OnInit } from '@angular/core';
 import { ActivatedRoute, Router } from '@angular/router';
@@ -8,7 +9,7 @@ import { BrowserStorageService } from '@v3/app/services/storage.service';
 import { Topic, TopicService } from '@v3/app/services/topic.service';
 import { UtilsService } from '@v3/app/services/utils.service';
 import { BehaviorSubject, Subscription } from 'rxjs';
-import { delay, filter, tap } from 'rxjs/operators';
+import { delay, filter, tap, distinctUntilChanged } from 'rxjs/operators';
 
 const SAVE_PROGRESS_TIMEOUT = 10000;
 
@@ -45,7 +46,8 @@ export class ActivityDesktopPage {
     private notificationsService: NotificationsService,
     private storageService: BrowserStorageService,
     private utils: UtilsService,
-    @Inject(DOCUMENT) private readonly document: Document
+    private unlockIndicatorService: UnlockIndicatorService,
+    @Inject(DOCUMENT) private readonly document: Document,
   ) { }
 
   ionViewWillEnter() {
@@ -60,10 +62,14 @@ export class ActivityDesktopPage {
       this.activityService.currentTask$.subscribe(res => this.currentTask = res)
     );
     this.subscriptions.push(
-      this.assessmentService.assessment$.subscribe(res => this.assessment = res)
+      this.assessmentService.assessment$
+        .pipe(distinctUntilChanged())
+        .subscribe(res => this.assessment = res)
     );
     this.subscriptions.push(
-      this.assessmentService.submission$.subscribe(res => this.submission = res)
+      this.assessmentService.submission$
+        .pipe(distinctUntilChanged())
+        .subscribe(res => this.submission = res)
     );
     this.subscriptions.push(
       this.assessmentService.review$.subscribe(res => this.review = res)
@@ -117,6 +123,7 @@ export class ActivityDesktopPage {
       });
     }));
 
+    // refresh when review is available (AI review, peer review, etc.)
     this.subscriptions.push(
       this.utils.getEvent('notification').subscribe(event => {
         const review = event?.meta?.AssessmentReview;
@@ -127,6 +134,17 @@ export class ActivityDesktopPage {
         }
       })
     );
+
+    // check new unlock indicator to refresh
+    this.subscriptions.push(
+      this.unlockIndicatorService.unlockedTasks$.subscribe(unlockedTasks => {
+        if (this.activity) {
+          if (unlockedTasks.some(task => task.activityId === this.activity.id)) {
+            this.activityService.getActivity(this.activity.id);
+          }
+        }
+      })
+    );
   }
 
   ionViewWillLeave() {
@@ -191,31 +209,67 @@ export class ActivityDesktopPage {
     this.btnDisabled$.next(true);
     this.savingText$.next('Saving...');
     try {
-      const saved = await this.assessmentService.submitAssessment(
-        event.submissionId,
-        event.assessmentId,
-        event.contextId,
-        event.answers
-      ).toPromise();
+      // handle unexpected submission: do final status check before saving
+      let hasSubmssion = false;
+      const { submission } = await this.assessmentService
+        .fetchAssessment(
+          event.assessmentId,
+          "assessment",
+          this.activity.id,
+          event.contextId,
+          event.submissionId
+        )
+        .toPromise();
 
-      // http 200 but error
-      if (saved?.data?.submitAssessment?.success !== true || this.utils.isEmpty(saved)) {
-        throw new Error("Error submitting assessment");
-      }
+      if (submission?.status === 'in progress') {
+        const saved = await this.assessmentService
+          .submitAssessment(
+            event.submissionId,
+            event.assessmentId,
+            event.contextId,
+            event.answers
+          )
+          .toPromise();
 
-      if (this.assessment.pulseCheck === true && event.autoSave === false) {
-        await this.assessmentService.pullFastFeedback();
+        // http 200 but error
+        if (
+          saved?.data?.submitAssessment?.success !== true ||
+          this.utils.isEmpty(saved)
+        ) {
+          throw new Error("Error submitting assessment");
+        }
+
+        if (this.assessment.pulseCheck === true && event.autoSave === false) {
+          await this.assessmentService.pullFastFeedback();
+        }
+      } else {
+        hasSubmssion = true;
       }
 
-      this.savingText$.next($localize `Last saved ${this.utils.getFormatedCurrentTime()}`);
+      this.savingText$.next(
+        $localize`Last saved ${this.utils.getFormatedCurrentTime()}`
+      );
+
       if (!event.autoSave) {
-        this.notificationsService.assessmentSubmittedToast();
+        if (hasSubmssion === true) {
+          this.notificationsService.assessmentSubmittedToast({ isDuplicated: true });
+        } else {
+          this.notificationsService.assessmentSubmittedToast();
+        }
+
+        await this.assessmentService.fetchAssessment(
+          event.assessmentId,
+          'assessment',
+          this.activity.id,
+          event.contextId,
+          event.submissionId
+        ).toPromise();
+
         // get the latest activity tasks
-        this.activityService.getActivity(this.activity.id, false, task, () => {
+        return this.activityService.getActivity(this.activity.id, false, task, () => {
           this.loading = false;
           this.btnDisabled$.next(false);
         });
-        return this.assessmentService.getAssessment(event.assessmentId, 'assessment', this.activity.id, event.contextId, event.submissionId);
       } else {
         setTimeout(() => {
           this.btnDisabled$.next(false);
diff --git a/projects/v3/src/app/pages/assessment-mobile/assessment-mobile.page.ts b/projects/v3/src/app/pages/assessment-mobile/assessment-mobile.page.ts
index bb2354d91..013314cdf 100644
--- a/projects/v3/src/app/pages/assessment-mobile/assessment-mobile.page.ts
+++ b/projects/v3/src/app/pages/assessment-mobile/assessment-mobile.page.ts
@@ -49,6 +49,7 @@ export class AssessmentMobilePage implements OnInit {
     this.assessmentService.submission$.subscribe(res => this.submission = res);
     this.assessmentService.review$.subscribe(res => this.review = res);
     this.route.params.subscribe(params => {
+      const assessmentId = +params.id;
       this.action = this.route.snapshot.data.action;
       this.fromPage = this.route.snapshot.data.from;
       if (!this.fromPage) {
@@ -57,7 +58,7 @@ export class AssessmentMobilePage implements OnInit {
       this.activityId = +params.activityId || 0;
       this.contextId = +params.contextId;
       this.submissionId = +params.submissionId;
-      this.assessmentService.getAssessment(+params.id, this.action, this.activityId, this.contextId, this.submissionId);
+      this.assessmentService.getAssessment(assessmentId, this.action, this.activityId, this.contextId, this.submissionId);
     });
   }
 
@@ -74,17 +75,6 @@ export class AssessmentMobilePage implements OnInit {
     };
   }
 
-  async continue() {
-    if (!this.currentTask) {
-      this.currentTask = this.task;
-    }
-    if (this.currentTask.status === 'done') {
-      // just go to the next task without any other action
-      return this.activityService.goToNextTask(this.currentTask);
-    }
-    // get the latest activity tasks and navigate to the next task
-    return this.activityService.getActivity(this.activityId, true, this.currentTask);
-  }
 
   goBack() {
     if (this.fromPage === 'reviews') {
@@ -106,7 +96,16 @@ export class AssessmentMobilePage implements OnInit {
     this.savingText$.next('Saving...');
 
     try {
-      if (this.action === 'assessment') {
+      let hasSubmission = false;
+      const { submission } = await this.assessmentService.fetchAssessment(
+        event.assessmentId,
+        this.action,
+        this.activityId,
+        event.contextId,
+        event.submissionId,
+      ).toPromise();
+
+      if (this.action === 'assessment' && submission.status === 'in progress') {
         const saved = await this.assessmentService.submitAssessment(
           event.submissionId,
           event.assessmentId,
@@ -119,7 +118,7 @@ export class AssessmentMobilePage implements OnInit {
           console.error('Asmt submission error:', saved);
           throw new Error("Error submitting assessment");
         }
-      } else if (this.action === 'review') {
+      } else if (this.action === 'review' && submission.status === 'pending review') {
         const saved = await this.assessmentService.submitReview(
           event.assessmentId,
           this.review.id,
@@ -134,6 +133,8 @@ export class AssessmentMobilePage implements OnInit {
         }
 
         this.reviewService.getReviews();
+      } else {
+        hasSubmission = true;
       }
 
       // [CORE-5876] - Fastfeedback is now added for reviewer
@@ -143,12 +144,30 @@ export class AssessmentMobilePage implements OnInit {
 
       this.savingText$.next($localize `Last saved ${this.utils.getFormatedCurrentTime()}`);
       if (!event.autoSave) {
-        this.notificationsService.assessmentSubmittedToast();
-        // get the latest activity tasks and refresh the assessment submission data
-        this.activityService.getActivity(this.activityId);
-        this.btnDisabled$.next(false);
-        this.saving = false;
-        return this.assessmentService.getAssessment(this.assessment.id, this.action, this.activityId, this.contextId, this.submissionId);
+        // show toast message
+        if (hasSubmission === true) {
+          this.notificationsService.assessmentSubmittedToast({ isDuplicated: true });
+        } else {
+          this.notificationsService.assessmentSubmittedToast({ isReview: this.action === 'review'});
+        }
+
+        await this.assessmentService.fetchAssessment(
+          this.assessment.id,
+          this.action,
+          this.activityId,
+          this.contextId,
+          this.submissionId
+        ).toPromise();
+
+        if (this.action === 'assessment') {
+          // get the latest activity tasks and refresh the assessment submission data
+          this.activityService.getActivity(this.activityId, false, null, () => {
+            this.btnDisabled$.next(false);
+          });
+        } else {
+          this.btnDisabled$.next(false);
+          this.saving = false;
+        }
       } else {
         setTimeout(() => {
           this.btnDisabled$.next(false);
@@ -168,9 +187,10 @@ export class AssessmentMobilePage implements OnInit {
       await this.reviewRatingPopUp();
       await this.notificationsService.getTodoItems().toPromise(); // update notifications list
 
-      this.btnDisabled$.next(false);
       // get the latest activity tasks and navigate to the next task
-      return this.activityService.getActivity(this.activityId, true, this.task);
+      return this.activityService.getActivity(this.activityId, true, this.task, () => {
+        this.btnDisabled$.next(false);
+      });
     } catch(err) {
       this.btnDisabled$.next(false);
       console.error(err);
@@ -178,7 +198,7 @@ export class AssessmentMobilePage implements OnInit {
   }
 
   nextTask() {
-    this.activityService.goToNextTask(this.task);
+    return this.activityService.getActivity(this.activityId, true, this.task);
   }
 
   async reviewRatingPopUp(): Promise<void> {
diff --git a/projects/v3/src/app/pages/experiences/experiences.page.html b/projects/v3/src/app/pages/experiences/experiences.page.html
index ca451866f..fbbfe8bcd 100644
--- a/projects/v3/src/app/pages/experiences/experiences.page.html
+++ b/projects/v3/src/app/pages/experiences/experiences.page.html
@@ -9,7 +9,7 @@ <h1 class="for-accessibility" i18n>Home</h1>
 </ion-header>
 
 <ion-content class="experience-page" [class]="{'mobile': isMobile}">
-  <ng-container *ngIf="(experiences$ | async ) as experiences">
+  <ng-container *ngIf="(experiences$ | async ) as experiences; else loading">
     <header>
       <h1 id="experiences" class="for-accessibility" i18n>Experiences</h1>
       <ion-grid class="ion-no-padding ion-no-margin">
@@ -72,3 +72,8 @@ <h1 class="headline-1 m-0 black ion-hide-sm-down" i18n>Your experiences</h1>
     </main>
   </ng-container>
 </ion-content>
+<ng-template #loading>
+  <div style="display: flex; justify-content: center; align-items: center; height: 100vh;">
+    <ion-spinner name="bubbles"></ion-spinner>
+  </div>
+</ng-template>
diff --git a/projects/v3/src/app/pages/experiences/experiences.page.ts b/projects/v3/src/app/pages/experiences/experiences.page.ts
index 7fddef91f..55861538c 100644
--- a/projects/v3/src/app/pages/experiences/experiences.page.ts
+++ b/projects/v3/src/app/pages/experiences/experiences.page.ts
@@ -55,9 +55,15 @@ export class ExperiencesPage implements OnInit, OnDestroy {
         const ids = experiences.map(experience => experience.projectId);
         this.experienceService.getProgresses(ids).subscribe(res => {
           res.forEach(progress => {
-            progress.forEach(project => {
-              this.progresses[project.id] = Math.round(progress.progress * 100);
-            });
+            if (Array.isArray(progress)) {
+              progress.forEach(project => {
+                this.progresses[project.id] = Math.round(project.progress * 100);
+              });
+              return;
+            }
+
+            // single progress objects
+            this.progresses[progress.id] = Math.round(progress.progress * 100);
           });
         });
       });
diff --git a/projects/v3/src/app/pages/home/home.page.ts b/projects/v3/src/app/pages/home/home.page.ts
index 7f8f90496..bd1b2ecd1 100644
--- a/projects/v3/src/app/pages/home/home.page.ts
+++ b/projects/v3/src/app/pages/home/home.page.ts
@@ -1,6 +1,9 @@
 import { Component, OnInit, OnDestroy } from '@angular/core';
 import { NavigationEnd, Router } from '@angular/router';
-import { Achievement, AchievementService } from '@v3/app/services/achievement.service';
+import {
+  Achievement,
+  AchievementService,
+} from '@v3/app/services/achievement.service';
 import { ActivityService } from '@v3/app/services/activity.service';
 import { AssessmentService } from '@v3/app/services/assessment.service';
 import { NotificationsService } from '@v3/app/services/notifications.service';
@@ -34,7 +37,7 @@ export class HomePage implements OnInit, OnDestroy {
   getIsPointsConfigured: boolean = false;
   getEarnedPoints: number = 0;
   hasUnlockedTasks: Object = {};
-  unlockedMilestones: {[key: number]: boolean} = {};
+  unlockedMilestones: { [key: number]: boolean } = {};
 
   // default card image (gracefully show broken url)
   defaultLeadImage: string = '';
@@ -57,57 +60,67 @@ export class HomePage implements OnInit, OnDestroy {
   ngOnInit() {
     this.isMobile = this.utils.isMobile();
     this.subscriptions = [];
-    this.subscriptions.push(this.homeService.milestones$.pipe(
-      distinctUntilChanged(),
-      filter(milestones => milestones !== null),
-    ).subscribe(
-      res => {
-        this.milestones = res;
-      }
-    ));
-    this.subscriptions.push(this.achievementService.achievements$.subscribe(
-      res => {
+    this.subscriptions.push(
+      this.homeService.milestones$
+        .pipe(
+          distinctUntilChanged(),
+          filter((milestones) => milestones !== null)
+        )
+        .subscribe((res) => {
+          this.milestones = res;
+        })
+    );
+    this.subscriptions.push(
+      this.achievementService.achievements$.subscribe((res) => {
         this.achievements = res;
-      }
-    ));
-    this.subscriptions.push(this.homeService.experienceProgress$.subscribe(
-      res => {
+      })
+    );
+    this.subscriptions.push(
+      this.homeService.experienceProgress$.subscribe((res) => {
         this.experienceProgress = res;
-      }
-    ));
-    this.subscriptions.push(this.homeService.projectProgress$.pipe(
-      filter(progress => progress !== null),
-    ).subscribe(
-      progress => {
-        progress?.milestones?.forEach(m => {
-          m.activities?.forEach(a => this.activityProgresses[a.id] = a.progress);
-        });
-      }
-    ));
+      })
+    );
+    this.subscriptions.push(
+      this.homeService.projectProgress$
+        .pipe(filter((progress) => progress !== null))
+        .subscribe((progress) => {
+          progress?.milestones?.forEach((m) => {
+            m.activities?.forEach(
+              (a) => (this.activityProgresses[a.id] = a.progress)
+            );
+          });
+        })
+    );
 
     this.subscriptions.push(
-      this.router.events.subscribe(event => {
+      this.router.events.subscribe((event) => {
         if (event instanceof NavigationEnd) {
           this.updateDashboard();
         }
       })
     );
 
-    this.unlockIndicatorService.unlockedTasks$.subscribe(unlockedTasks => {
+    this.unlockIndicatorService.unlockedTasks$.subscribe((unlockedTasks) => {
       this.hasUnlockedTasks = {}; // reset
       this.unlockedMilestones = {}; // reset
-      unlockedTasks.forEach(task => {
+      unlockedTasks.forEach((task) => {
         if (task.milestoneId) {
-          this.unlockedMilestones[task.milestoneId] = true;
+          if (this.unlockIndicatorService.isMilestoneClearable(task.milestoneId)) {
+            this.verifyUnlockedMilestoneValidity(task.milestoneId);
+          } else {
+            this.unlockedMilestones[task.milestoneId] = true;
+          }
         }
 
-        this.hasUnlockedTasks[task.activityId] = true;
+        if (task.activityId) {
+          this.hasUnlockedTasks[task.activityId] = true;
+        }
       });
     });
   }
 
   ngOnDestroy(): void {
-    this.subscriptions.forEach(s => s.unsubscribe());
+    this.subscriptions.forEach((s) => s.unsubscribe());
   }
 
   async updateDashboard() {
@@ -170,32 +183,27 @@ export class HomePage implements OnInit, OnDestroy {
    * @param keyboardEvent The keyboard event object, if the function was called by a keyboard event.
    * @returns A Promise that resolves when the navigation is complete.
    */
-  async gotoActivity({activity, milestone}, keyboardEvent?: KeyboardEvent) {
-    if (keyboardEvent && (keyboardEvent?.code === 'Space' || keyboardEvent?.code === 'Enter')) {
+  async gotoActivity({ activity, milestone }, keyboardEvent?: KeyboardEvent) {
+    if (
+      keyboardEvent &&
+      (keyboardEvent?.code === 'Space' || keyboardEvent?.code === 'Enter')
+    ) {
       keyboardEvent.preventDefault();
     } else if (keyboardEvent) {
       return;
     }
 
     if (activity.isLocked) {
-      return ;
+      return;
     }
 
     this.activityService.clearActivity();
     this.assessmentService.clearAssessment();
 
-    // check & update unlocked milestones
     if (this.unlockIndicatorService.isMilestoneClearable(milestone.id)) {
-      const unlockedMilestones = this.unlockIndicatorService.clearActivity(milestone.id);
-      unlockedMilestones.forEach(unlockedMilestone => {
-        this.notification.markTodoItemAsDone(unlockedMilestone).pipe(first()).subscribe(() => {
-          // eslint-disable-next-line no-console
-          console.log('Marked milestone as done', unlockedMilestone);
-        });
-      });
+      this.verifyUnlockedMilestoneValidity(milestone.id);
     }
 
-
     if (!this.isMobile) {
       return this.router.navigate(['v3', 'activity-desktop', activity.id]);
     }
@@ -203,8 +211,26 @@ export class HomePage implements OnInit, OnDestroy {
     return this.router.navigate(['v3', 'activity-mobile', activity.id]);
   }
 
+  verifyUnlockedMilestoneValidity(milestoneId: number): void {
+    // check & update unlocked milestones
+    const unlockedMilestones =
+      this.unlockIndicatorService.clearActivity(milestoneId);
+    unlockedMilestones.forEach((unlockedMilestone) => {
+      this.notification
+        .markTodoItemAsDone(unlockedMilestone)
+        .pipe(first())
+        .subscribe(() => {
+          // eslint-disable-next-line no-console
+          console.log('Marked milestone as done', unlockedMilestone);
+        });
+    });
+  }
+
   achievePopup(achievement: Achievement, keyboardEvent?: KeyboardEvent): void {
-    if (keyboardEvent && (keyboardEvent?.code === 'Space' || keyboardEvent?.code === 'Enter')) {
+    if (
+      keyboardEvent &&
+      (keyboardEvent?.code === 'Space' || keyboardEvent?.code === 'Enter')
+    ) {
       keyboardEvent.preventDefault();
     } else if (keyboardEvent) {
       return;
diff --git a/projects/v3/src/app/pages/review-desktop/review-desktop.page.ts b/projects/v3/src/app/pages/review-desktop/review-desktop.page.ts
index 7e5fe1efe..81104873d 100644
--- a/projects/v3/src/app/pages/review-desktop/review-desktop.page.ts
+++ b/projects/v3/src/app/pages/review-desktop/review-desktop.page.ts
@@ -96,29 +96,51 @@ export class ReviewDesktopPage implements OnInit {
     this.btnDisabled$.next(true);
     this.savingText$.next('Saving...');
     try {
-      const res = await this.assessmentService.submitReview(
-        this.assessment.id,
-        this.review.id,
-        this.submission.id,
-        event.answers
-      ).toPromise();
-
-      // [CORE-5876] - Fastfeedback is now added for reviewer
-      if (this.assessment.pulseCheck === true && event.autoSave === false) {
-        await this.assessmentService.pullFastFeedback();
-      }
+      const { submission } = await this.assessmentService
+        .fetchAssessment(
+          event.assessmentId,
+          "review",
+          null,
+          this.currentReview.contextId,
+          this.submission.id
+        )
+        .toPromise();
 
-      this.assessmentService.getAssessment(this.assessment.id, 'review', 0, this.currentReview.contextId, this.submission.id);
-      this.reviewService.getReviews();
+      if (submission.status === 'pending review') {
+        const res = await this.assessmentService.submitReview(
+          this.assessment.id,
+          this.review.id,
+          this.submission.id,
+          event.answers
+        ).toPromise();
+
+        // [CORE-5876] - Fastfeedback is now added for reviewer
+        if (this.assessment.pulseCheck === true && event.autoSave === false) {
+          await this.assessmentService.pullFastFeedback();
+        }
+
+        await this.assessmentService.fetchAssessment(
+          this.assessment.id,
+          'review',
+          0,
+          this.currentReview.contextId,
+          this.submission.id
+        ).toPromise();
+        this.reviewService.getReviews();
+
+        await this.notificationsService.getTodoItems().toPromise(); // update notifications list
 
-      await this.notificationsService.getTodoItems().toPromise(); // update notifications list
+        // fail gracefully: Review submission API may sometimes fail silently
+        if (res?.data?.submitReview === false) {
+          this.savingText$.next($localize`Save failed.`);
+          this.btnDisabled$.next(false);
+          this.loading = false;
+          return;
+        }
 
-      // fail gracefully: Review submission API may sometimes fail silently
-      if (res?.data?.submitReview === false) {
-        this.savingText$.next($localize`Save failed.`);
-        this.btnDisabled$.next(false);
-        this.loading = false;
-        return;
+        this.notificationsService.assessmentSubmittedToast({ isReview: true });
+      } else {
+        this.notificationsService.assessmentSubmittedToast({ isDuplicated: true });
       }
 
       this.loading = false;
diff --git a/projects/v3/src/app/services/assessment.service.spec.ts b/projects/v3/src/app/services/assessment.service.spec.ts
index ef8b5e8b8..ea334afe5 100644
--- a/projects/v3/src/app/services/assessment.service.spec.ts
+++ b/projects/v3/src/app/services/assessment.service.spec.ts
@@ -578,4 +578,48 @@ describe('AssessmentService', () => {
     });
   });
 
+  describe('_normaliseAnswer', () => {
+    beforeEach(() => {
+      service.questions = {
+        1: { type: 'oneof', choices: [] },
+        2: { type: 'multiple', choices: [] },
+        3: { type: 'multi team member selector', choices: [] }
+      };
+    });
+
+    it('should convert string to number for oneof question type', () => {
+      const result = service['_normaliseAnswer'](1, '123');
+      expect(result).toEqual(123);
+    });
+
+    it('should convert empty string to null for oneof question type', () => {
+      const result = service['_normaliseAnswer'](1, '');
+      expect(result).toBeNull();
+    });
+
+    it('should convert string to array for multiple question type', () => {
+      const result = service['_normaliseAnswer'](2, '[1,2,3]');
+      expect(result).toEqual([1, 2, 3]);
+    });
+
+    it('should handle non-array string by wrapping it in an array for multiple question type', () => {
+      const result = service['_normaliseAnswer'](2, 'not an array');
+      expect(result).toEqual(['not an array']);
+    });
+
+    it('should parse string to array for multi team member selector question type', () => {
+      const result = service['_normaliseAnswer'](3, '[1,2,3]');
+      expect(result).toEqual([1, 2, 3]);
+    });
+
+    it('should return the answer as is for invalid question type', () => {
+      const result = service['_normaliseAnswer'](999, 'test');
+      expect(result).toEqual('test');
+    });
+
+    it('should return the answer as is if question not found', () => {
+      const result = service['_normaliseAnswer'](4, 'test'); // Assuming questionId 4 does not exist
+      expect(result).toEqual('test');
+    });
+  });
 });
diff --git a/projects/v3/src/app/services/assessment.service.ts b/projects/v3/src/app/services/assessment.service.ts
index fcccc4de8..4675e7d99 100644
--- a/projects/v3/src/app/services/assessment.service.ts
+++ b/projects/v3/src/app/services/assessment.service.ts
@@ -1,6 +1,6 @@
 import { Injectable } from '@angular/core';
-import { Observable as RxObsservable, BehaviorSubject, of, Subscription } from 'rxjs';
-import { map, shareReplay } from 'rxjs/operators';
+import { Observable, BehaviorSubject, of, Subscription } from 'rxjs';
+import { map, shareReplay, catchError } from 'rxjs/operators';
 import { UtilsService } from '@v3/services/utils.service';
 import { BrowserStorageService } from '@v3/services/storage.service';
 import { NotificationsService } from '@v3/services/notifications.service';
@@ -109,7 +109,6 @@ export interface AssessmentReview {
 @Injectable({
   providedIn: 'root'
 })
-
 export class AssessmentService {
   private _assessment$ = new BehaviorSubject<Assessment>(null);
   assessment$ = this._assessment$.pipe(shareReplay(1));
@@ -131,33 +130,27 @@ export class AssessmentService {
     private demo: DemoService,
     private request: RequestService,
   ) {
-    this.assessment$.subscribe(res => this.assessment = res);
+    this.assessment$.subscribe((res) => (this.assessment = res));
   }
 
   clearAssessment() {
     this._assessment$.next(null);
   }
 
-  /**
-   * shared among reviewing & assessment answering page
-   *
-   * @param   {number}  id            assessment id
-   * @param   {string}  action        review/assessment (reviewing or answering)
-   * @param   {number}  activityId    activity id
-   * @param   {number}  contextId     context id (activity & task related)
-   * @param   {number}  submissionId  optional submission id
-   *
-   * @return  {Subscription}          no need to unsubscribe, handled by apollo
-   */
-  getAssessment(id, action, activityId, contextId, submissionId?): Subscription {
-    if (!this.assessment || this.assessment.id !== id) {
-      this.clearAssessment();
-    }
-    if (environment.demo) {
-      return this.demo.assessment(id).pipe(map(res => this._handleAssessmentResponse(res, action))).subscribe();
-    }
-    return this.apolloService.graphQLWatch(
-      `query getAssessment($assessmentId: Int!, $reviewer: Boolean!, $activityId: Int!, $contextId: Int!, $submissionId: Int) {
+  fetchAssessment(
+    id: number,
+    action: string,
+    activityId: number,
+    contextId: number,
+    submissionId?: number
+  ): Observable<{
+    assessment: Assessment;
+    submission: Submission;
+    review: AssessmentReview;
+  }> {
+    return this.apolloService
+      .graphQLFetch(
+        `query getAssessment($assessmentId: Int!, $reviewer: Boolean!, $activityId: Int!, $contextId: Int!, $submissionId: Int) {
         assessment(id:$assessmentId, reviewer:$reviewer, activityId:$activityId, submissionId:$submissionId) {
           id name type description dueDate isTeam pulseCheck allowResubmit
           groups{
@@ -193,35 +186,78 @@ export class AssessmentService {
           }
         }
       }`,
-      {
-        assessmentId: +id,
-        reviewer: action === 'review',
-        activityId: +activityId,
-        submissionId: +submissionId || null,
-        contextId: +contextId
-      },
-      {
-        noCache: true
-      }
-    ).pipe(
-      map(res => this._handleAssessmentResponse(res, action))
+        {
+          variables: {
+            assessmentId: id,
+            reviewer: action === 'review',
+            activityId: +activityId,
+            submissionId: +submissionId || null,
+            contextId: +contextId,
+          },
+        },
+      )
+      .pipe(map((res) => this._handleAssessmentResponse(res, action)));
+  }
+
+  /**
+   * shared among reviewing & assessment answering page
+   *
+   * @param   {number}  id            assessment id
+   * @param   {string}  action        review/assessment (reviewing or answering)
+   * @param   {number}  activityId    activity id
+   * @param   {number}  contextId     context id (activity & task related)
+   * @param   {number}  submissionId  optional submission id
+   *
+   * @return  {Subscription}          no need to unsubscribe, handled by apollo
+   */
+  getAssessment(
+    id,
+    action,
+    activityId,
+    contextId,
+    submissionId?
+  ): Subscription {
+    if (!this.assessment || this.assessment.id !== id) {
+      this.clearAssessment();
+    }
+    if (environment.demo) {
+      return this.demo
+        .assessment(id)
+        .pipe(map((res) => this._handleAssessmentResponse(res, action)))
+        .subscribe();
+    }
+    return this.fetchAssessment(
+      id,
+      action,
+      activityId,
+      contextId,
+      submissionId
     ).subscribe();
   }
 
-  private _handleAssessmentResponse(res, action) {
+  private _handleAssessmentResponse(
+    res,
+    action
+  ): {
+    assessment: Assessment;
+    submission: Submission;
+    review: AssessmentReview;
+  } {
     if (!res) {
       return null;
     }
+
     const assessment = this._normaliseAssessment(res.data, action);
     const submission = this._normaliseSubmission(res.data);
     const review = this._normaliseReview(res.data, action);
     this._assessment$.next(assessment);
     this._submission$.next(submission);
     this._review$.next(review);
+
     return {
       assessment,
       submission,
-      review
+      review,
     };
   }
 
@@ -236,17 +272,19 @@ export class AssessmentService {
       description: data.assessment.description,
       isForTeam: data.assessment.isTeam,
       dueDate: data.assessment.dueDate,
-      isOverdue: data.assessment.dueDate ? this.utils.timeComparer(data.assessment.dueDate) < 0 : false,
+      isOverdue: data.assessment.dueDate
+        ? this.utils.timeComparer(data.assessment.dueDate) < 0
+        : false,
       pulseCheck: data.assessment.pulseCheck,
       allowResubmit: data.assessment.allowResubmit,
-      groups: []
+      groups: [],
     };
-    data.assessment.groups.forEach(eachGroup => {
+    data.assessment.groups.forEach((eachGroup) => {
       const questions: Question[] = [];
       if (!eachGroup.questions) {
         return;
       }
-      eachGroup.questions.forEach(eachQuestion => {
+      eachGroup.questions.forEach((eachQuestion) => {
         this.questions[eachQuestion.id] = eachQuestion;
         const question: Question = {
           id: eachQuestion.id,
@@ -255,10 +293,17 @@ export class AssessmentService {
           description: eachQuestion.description,
           isRequired: eachQuestion.isRequired,
           canComment: eachQuestion.hasComment,
-          canAnswer: action === 'review' ? eachQuestion.audience.includes('reviewer') : eachQuestion.audience.includes('submitter'),
+          canAnswer:
+            action === 'review'
+              ? eachQuestion.audience.includes('reviewer')
+              : eachQuestion.audience.includes('submitter'),
           audience: eachQuestion.audience,
-          submitterOnly: eachQuestion.audience.length === 1 && eachQuestion.audience.includes('submitter'),
-          reviewerOnly: eachQuestion.audience.length === 1 && eachQuestion.audience.includes('reviewer')
+          submitterOnly:
+            eachQuestion.audience.length === 1 &&
+            eachQuestion.audience.includes('submitter'),
+          reviewerOnly:
+            eachQuestion.audience.length === 1 &&
+            eachQuestion.audience.includes('reviewer'),
         };
         switch (eachQuestion.type) {
           case 'oneof':
@@ -269,7 +314,11 @@ export class AssessmentService {
               choices.push({
                 id: eachChoice.id,
                 name: eachChoice.name,
-                explanation: eachChoice.explanation ? this.sanitizer.bypassSecurityTrustHtml(eachChoice.explanation) : null,
+                explanation: eachChoice.explanation
+                  ? this.sanitizer.bypassSecurityTrustHtml(
+                      eachChoice.explanation
+                    )
+                  : null,
               });
               if (eachChoice.description) {
                 info += '<p>' + eachChoice.name + ' - ' + eachChoice.description + '</p>';
@@ -290,10 +339,10 @@ export class AssessmentService {
           case 'team member selector':
           case 'multi team member selector':
             question.teamMembers = [];
-            eachQuestion.teamMembers.forEach(eachTeamMember => {
+            eachQuestion.teamMembers.forEach((eachTeamMember) => {
               question.teamMembers.push({
                 key: JSON.stringify(eachTeamMember),
-                userName: eachTeamMember.userName
+                userName: eachTeamMember.userName,
               });
             });
             break;
@@ -304,7 +353,7 @@ export class AssessmentService {
         assessment.groups.push({
           name: eachGroup.name,
           description: eachGroup.description,
-          questions: questions
+          questions: questions,
         });
       }
     });
@@ -312,9 +361,13 @@ export class AssessmentService {
   }
 
   private _normaliseSubmission(data): Submission {
-    if (!this.utils.has(data, 'assessment.submissions') || data.assessment.submissions.length < 1) {
+    if (
+      !this.utils.has(data, "assessment.submissions") ||
+      data.assessment.submissions.length < 1
+    ) {
       return null;
     }
+
     const firstSubmission = data.assessment.submissions[0];
     let submission: Submission = {
       id: firstSubmission.id,
@@ -324,18 +377,25 @@ export class AssessmentService {
       modified: firstSubmission.modified,
       isLocked: firstSubmission.locked,
       completed: firstSubmission.completed,
-      reviewerName: firstSubmission.review ? this.checkReviewer(firstSubmission.review.reviewer) : null,
-      answers: {}
+      reviewerName: firstSubmission.review
+        ? this.checkReviewer(firstSubmission.review.reviewer)
+        : null,
+      answers: {},
     };
-    firstSubmission.answers.forEach(eachAnswer => {
-      eachAnswer.answer = this._normaliseAnswer(eachAnswer.questionId, eachAnswer.answer);
+
+    firstSubmission.answers.forEach((eachAnswer) => {
+      eachAnswer.answer = this._normaliseAnswer(
+        eachAnswer.questionId,
+        eachAnswer.answer
+      );
       submission.answers[eachAnswer.questionId] = {
-        answer: eachAnswer.answer
+        answer: eachAnswer.answer,
       };
       if (['published', 'done'].includes(submission.status)) {
         submission = this._addChoiceExplanation(eachAnswer, submission);
       }
     });
+
     return submission;
   }
 
@@ -351,7 +411,10 @@ export class AssessmentService {
   }
 
   private _normaliseReview(data, action: string): AssessmentReview {
-    if (!this.utils.has(data, 'assessment.submissions') || data.assessment.submissions.length < 1) {
+    if (
+      !this.utils.has(data, 'assessment.submissions') ||
+      data.assessment.submissions.length < 1
+    ) {
       return null;
     }
     const firstSubmission = data.assessment.submissions[0];
@@ -364,7 +427,7 @@ export class AssessmentService {
       status: firstSubmissionReview.status,
       modified: firstSubmissionReview.modified,
       teamName: firstSubmission.submitter.team?.name,
-      answers: {}
+      answers: {},
     };
 
     // only get the review answer if the review is published, or it is for the reviewer to see the review
@@ -373,11 +436,14 @@ export class AssessmentService {
       return review;
     }
 
-    firstSubmissionReview.answers.forEach(eachAnswer => {
-      eachAnswer.answer = this._normaliseAnswer(eachAnswer.questionId, eachAnswer.answer);
+    firstSubmissionReview.answers.forEach((eachAnswer) => {
+      eachAnswer.answer = this._normaliseAnswer(
+        eachAnswer.questionId,
+        eachAnswer.answer
+      );
       review.answers[eachAnswer.questionId] = {
         answer: eachAnswer.answer,
-        comment: eachAnswer.comment
+        comment: eachAnswer.comment,
       };
     });
     return review;
@@ -386,7 +452,10 @@ export class AssessmentService {
   /**
    * For each question that has choice (oneof & multiple), show the choice explanation in the submission if it is not empty
    */
-  private _addChoiceExplanation(submissionAnswer, submission: Submission): Submission {
+  private _addChoiceExplanation(
+    submissionAnswer,
+    submission: Submission
+  ): Submission {
     const questionId = submissionAnswer.questionId;
     const answer = submissionAnswer.answer;
     // don't do anything if there's no choices
@@ -396,7 +465,7 @@ export class AssessmentService {
     let explanation = '';
     if (Array.isArray(answer)) {
       // multiple question
-      this.questions[questionId].choices.forEach(choice => {
+      this.questions[questionId].choices.forEach((choice) => {
         // only display the explanation if it is not empty
         if (answer.includes(choice.id) && !this.utils.isEmpty(choice.explanation)) {
           explanation += choice.name + ' - ' + choice.explanation + '\n';
@@ -404,7 +473,7 @@ export class AssessmentService {
       });
     } else {
       // oneof question
-      this.questions[questionId].choices.forEach(choice => {
+      this.questions[questionId].choices.forEach((choice) => {
         // only display the explanation if it is not empty
         if (answer === choice.id && !this.utils.isEmpty(choice.explanation)) {
           explanation = choice.explanation;
@@ -415,8 +484,12 @@ export class AssessmentService {
       return submission;
     }
     // put the explanation in the submission
-    const thisExplanation = explanation.replace(/text-align: center;/gi, 'text-align: center; text-align: -webkit-center;');
-    submission.answers[questionId].explanation = this.sanitizer.bypassSecurityTrustHtml(thisExplanation);
+    const thisExplanation = explanation.replace(
+      /text-align: center;/gi,
+      "text-align: center; text-align: -webkit-center;"
+    );
+    submission.answers[questionId].explanation =
+      this.sanitizer.bypassSecurityTrustHtml(thisExplanation);
 
     return submission;
   }
@@ -433,18 +506,27 @@ export class AssessmentService {
             answer = +answer;
           }
           break;
+
         case 'multiple':
+          // Check if answer is empty or not an array, and attempt to parse if it's a string
           if (this.utils.isEmpty(answer)) {
             answer = [];
+          } else if (typeof answer === 'string') {
+            try {
+              answer = JSON.parse(answer);
+            } catch (e) {
+              // In case JSON.parse fails, wrap the original answer in an array
+              answer = [answer];
+            }
           }
+
+          // Ensure answer is an array (wrap non-array values in an array)
           if (!Array.isArray(answer)) {
-            // re-format json string to array
-            answer = JSON.parse(answer);
+            answer = [answer];
           }
-          // re-format answer from string to number
-          answer = answer.map(value => {
-            return +value;
-          });
+
+          // Convert all elements to numbers
+          answer = answer.map(value => +(value || NaN));
           break;
 
         case 'multi team member selector':
@@ -470,20 +552,23 @@ export class AssessmentService {
       questionId,
       answer,
     };
-    return this.apolloService.continuousGraphQLMutate(
-      `mutation saveSubmissionAnswer(${paramsFormat}) {
+    return this.apolloService
+      .continuousGraphQLMutate(
+        `mutation saveSubmissionAnswer(${paramsFormat}) {
         saveSubmissionAnswer(${params}) {
           success
           message
         }
       }`,
       variables
-    ).pipe(map(res => {
-      if (!this.isValidData('saveQuestionAnswer', res)) {
-        throw new Error('Autosave: Invalid API data');
-      }
-      return res;
-    }));
+    ).pipe(
+      map(res => {
+        if (!this.isValidData('saveQuestionAnswer', res)) {
+          throw new Error('Autosave: Invalid API data');
+        }
+        return res;
+      })
+    );
   }
 
   /**
@@ -536,8 +621,9 @@ export class AssessmentService {
       answer,
       comment,
     };
-    return this.apolloService.continuousGraphQLMutate(
-      `mutation saveReviewAnswer(${paramsFormat}) {
+    return this.apolloService
+      .continuousGraphQLMutate(
+        `mutation saveReviewAnswer(${paramsFormat}) {
         saveReviewAnswer(${params}) {
           success
           message
@@ -553,26 +639,50 @@ export class AssessmentService {
   }
 
   // set the status of the submission to 'done' or 'pending approval'
-  submitAssessment(submissionId: number, assessmentId: number, contextId: number, answers: Answer[]) {
-    const paramsFormat = '$submissionId: Int!, $assessmentId: Int!, $contextId: Int!, $answers: [AssessmentSubmissionAnswerInput]';
-    const params = 'submissionId:$submissionId, assessmentId:$assessmentId, contextId:$contextId, answers:$answers';
+  submitAssessment(
+    submissionId: number,
+    assessmentId: number,
+    contextId: number,
+    answers: Answer[]
+  ) {
+    const paramsFormat =
+      '$submissionId: Int!, $assessmentId: Int!, $contextId: Int!, $answers: [AssessmentSubmissionAnswerInput]';
+    const params =
+      'submissionId:$submissionId, assessmentId:$assessmentId, contextId:$contextId, answers:$answers';
     const variables = {
       submissionId,
       assessmentId,
       contextId,
       answers,
     };
-    return this.apolloService.graphQLMutate(
-      `mutation submitAssessment(${paramsFormat}) {
+    return this.apolloService
+      .graphQLMutate(
+        `mutation submitAssessment(${paramsFormat}) {
         submitAssessment(${params})
       }`,
       variables
-    ).pipe(map(res => {
-      if (!this.isValidData('submitAssessment', res)) {
-        throw new Error('Submission: Invalid API data');
-      }
-      return res;
-    }));
+    ).pipe(
+      map((res) => {
+        if (!this.isValidData('submitAssessment', res)) {
+          throw new Error('Submission: Invalid API data');
+        }
+        return res;
+      }),
+      catchError(error => {
+        if (error.status === 429) {
+          // If the error is a 429, return a successful Observable
+          return of({
+            data: {
+              submitAssessment: {
+                success: true,
+                message: 'Rate limit exceeded, treated as success'
+              },
+            },
+          });
+        }
+        throw error;
+      })
+    );
   }
 
   /**
@@ -581,30 +691,46 @@ export class AssessmentService {
    * @param reviewId - review id
    * @param submissionId - submission id
    * @returns
-    */
-  submitReview(assessmentId: number, reviewId: number, submissionId: number, answers: Answer[]) {
-    const paramsFormat = '$assessmentId: Int!, $reviewId: Int!, $submissionId: Int!, $answers: [AssessmentReviewAnswerInput]';
-    const params = 'assessmentId:$assessmentId, reviewId:$reviewId, submissionId:$submissionId, answers:$answers';
+   */
+  submitReview(
+    assessmentId: number,
+    reviewId: number,
+    submissionId: number,
+    answers: Answer[]
+  ) {
+    const paramsFormat =
+      '$assessmentId: Int!, $reviewId: Int!, $submissionId: Int!, $answers: [AssessmentReviewAnswerInput]';
+    const params =
+      'assessmentId:$assessmentId, reviewId:$reviewId, submissionId:$submissionId, answers:$answers';
     const variables = {
       assessmentId,
       reviewId,
       submissionId,
       answers,
     };
-    return this.apolloService.graphQLMutate(
-      `mutation submitReview(${paramsFormat}) {
+    return this.apolloService
+      .graphQLMutate(
+        `mutation submitReview(${paramsFormat}) {
         submitReview(${params})
       }`,
-      variables
-    ).pipe(map(res => {
-      if (!this.isValidData('submitReview', res)) {
-        throw new Error('Submission: Invalid API data');
-      }
-      return res;
-    }));
+        variables
+      )
+      .pipe(
+        map((res) => {
+          if (!this.isValidData('submitReview', res)) {
+            throw new Error('Submission: Invalid API data');
+          }
+          return res;
+        })
+      );
   }
 
-  saveAnswers(assessment: AssessmentSubmitParams, answers: Answer[], action: string, hasPulseCheck: boolean) {
+  saveAnswers(
+    assessment: AssessmentSubmitParams,
+    answers: Answer[],
+    action: string,
+    hasPulseCheck: boolean
+  ) {
     if (!['assessment', 'review'].includes(action)) {
       return of(false);
     }
@@ -613,37 +739,53 @@ export class AssessmentService {
       this._afterSubmit(assessment, answers, action, hasPulseCheck);
       return this.demo.normalResponse();
     }
-    let paramsFormat = `$assessmentId: Int!, $inProgress: Boolean, $answers: [${(action === 'assessment' ? 'AssessmentSubmissionAnswerInput' : 'AssessmentReviewAnswerInput')}]`;
-    let params = 'assessmentId:$assessmentId, inProgress:$inProgress, answers:$answers';
+    let paramsFormat = `$assessmentId: Int!, $inProgress: Boolean, $answers: [${
+      action === 'assessment'
+        ? 'AssessmentSubmissionAnswerInput'
+        : 'AssessmentReviewAnswerInput'
+    }]`;
+    let params =
+      'assessmentId:$assessmentId, inProgress:$inProgress, answers:$answers';
     const variables = {
       assessmentId: assessment.id,
       inProgress: assessment.inProgress,
-      answers: answers
+      answers: answers,
     };
     [
       { key: 'submissionId', type: 'Int' },
       { key: 'contextId', type: 'Int!' },
       { key: 'reviewId', type: 'Int' },
-      { key: 'unlock', type: 'Boolean' }
-    ].forEach(item => {
+      { key: 'unlock', type: 'Boolean' },
+    ].forEach((item) => {
       if (assessment[item.key]) {
         paramsFormat += `, $${item.key}: ${item.type}`;
         params += `,${item.key}: $${item.key}`;
         variables[item.key] = assessment[item.key];
       }
     });
-    return this.apolloService.graphQLMutate(
-      `mutation saveAnswers(${paramsFormat}){
-        ` + (action === 'assessment' ? `submitAssessment` : `submitReview`) + `(${params})
+    return this.apolloService
+      .graphQLMutate(
+        `mutation saveAnswers(${paramsFormat}){
+        ` +
+          (action === 'assessment' ? `submitAssessment` : `submitReview`) +
+          `(${params})
       }`,
-      variables
-    ).pipe(map(res => {
-      this._afterSubmit(assessment, answers, action, hasPulseCheck);
-      return res;
-    }));
+        variables
+      )
+      .pipe(
+        map((res) => {
+          this._afterSubmit(assessment, answers, action, hasPulseCheck);
+          return res;
+        })
+      );
   }
 
-  private _afterSubmit(assessment: AssessmentSubmitParams, answers: Answer[], action: string, hasPulseCheck: boolean) {
+  private _afterSubmit(
+    assessment: AssessmentSubmitParams,
+    answers: Answer[],
+    action: string,
+    hasPulseCheck: boolean
+  ) {
     if (hasPulseCheck && !assessment.inProgress) {
       this.pullFastFeedback();
     }
@@ -655,7 +797,9 @@ export class AssessmentService {
    */
   async pullFastFeedback() {
     try {
-      const modal = await this.fastFeedbackService.pullFastFeedback({ modalOnly: true }).toPromise();
+      const modal = await this.fastFeedbackService
+        .pullFastFeedback({ modalOnly: true })
+        .toPromise();
       if (modal && modal.present) {
         await modal.present();
         await modal.onDidDismiss();
@@ -663,7 +807,7 @@ export class AssessmentService {
     } catch (err) {
       const toasted = await this.NotificationsService.alert({
         header: $localize`Error retrieving pulse check data`,
-        message: err.msg || JSON.stringify(err)
+        message: err.msg || JSON.stringify(err),
       });
       throw new Error(err);
     }
@@ -675,7 +819,7 @@ export class AssessmentService {
       return of(true);
     }
     return this.NotificationsService.markTodoItemAsDone({
-      identifier: 'AssessmentSubmission-' + submissionId
+      identifier: 'AssessmentSubmission-' + submissionId,
     });
   }
 
@@ -689,13 +833,13 @@ export class AssessmentService {
   resubmitAssessment({
     assessment_id,
     submission_id,
-  }): RxObsservable<any> {
+  }): Observable<any> {
     return this.request.post({
       endPoint: api.post.resubmit,
-      data:{
+      data: {
         assessment_id,
         submission_id,
-      }
+      },
     });
   }
 }
diff --git a/projects/v3/src/app/services/network.service.ts b/projects/v3/src/app/services/network.service.ts
index 464d8033d..06090034c 100644
--- a/projects/v3/src/app/services/network.service.ts
+++ b/projects/v3/src/app/services/network.service.ts
@@ -1,19 +1,30 @@
 import { Injectable } from '@angular/core';
+import { RequestService } from 'request';
 import { Observable, fromEvent, merge, of } from 'rxjs';
-import { mapTo } from 'rxjs/operators';
+import { map, switchMap, startWith, distinctUntilChanged, catchError } from 'rxjs/operators';
 
 @Injectable({
   providedIn: 'root'
 })
 export class NetworkService {
+  private online$: Observable<boolean>;
 
-  private online$: Observable<boolean> = undefined;
-
-  constructor() {
+  constructor(private request: RequestService) {
     this.online$ = merge(
       of(navigator.onLine),
-      fromEvent(window, 'online').pipe(mapTo(true)),
-      fromEvent(window, 'offline').pipe(mapTo(false))
+      fromEvent(window, 'online').pipe(map(() => true)),
+      fromEvent(window, 'offline').pipe(map(() => false))
+    ).pipe(
+      switchMap(isOnline => {
+        if (!isOnline) {
+          // When offline, check server reachability
+          return this.checkServerReachability().pipe(
+            startWith(false)
+          );
+        }
+        return of(isOnline);
+      }),
+      distinctUntilChanged() // Emit only when the online status actually changes
     );
   }
 
@@ -21,4 +32,11 @@ export class NetworkService {
     return this.online$;
   }
 
+  private checkServerReachability(): Observable<boolean> {
+    return this.request.get('https://practera.com', { observe: 'response' })
+      .pipe(
+        map(response => response.status === 200),
+        catchError(() => of(false))
+      );
+  }
 }
diff --git a/projects/v3/src/app/services/notifications.service.ts b/projects/v3/src/app/services/notifications.service.ts
index a1616d45d..dddced1c8 100644
--- a/projects/v3/src/app/services/notifications.service.ts
+++ b/projects/v3/src/app/services/notifications.service.ts
@@ -233,13 +233,23 @@ export class NotificationsService {
    * @return  {Promise<void>}
    */
   assessmentSubmittedToast(option?: {
-    isFail: boolean;
+    isDuplicated?: boolean;
+    isFail?: boolean;
+    isReview?: boolean;
     label?: string;
   }): void | Promise<void> {
     if (!this.connection.isOnline) {
       return alert('You are offline, please check your internet connection and try again.');
     }
 
+    if (option?.isDuplicated === true) {
+      return this.presentToast($localize`Duplicated submission detected. Your submission is already in our system.`, {
+        color: 'success',
+        icon: 'checkmark-circle'
+      });
+    }
+
+    // fail message
     if (option?.isFail === true) {
       if (option?.label) {
         return this.presentToast(option.label, {
@@ -253,7 +263,10 @@ export class NotificationsService {
         icon: 'close-circle'
       });
     }
-    return this.presentToast($localize`Assessment Submitted.`, {
+
+    // success by default
+    const message = option?.isReview === true ? $localize`Review Submitted.` : $localize`Assessment Submitted.`;
+    return this.presentToast(message, {
       color: 'success',
       icon: 'checkmark-circle'
     });
diff --git a/projects/v3/src/app/services/unlock-indicator.service.ts b/projects/v3/src/app/services/unlock-indicator.service.ts
index b6a113f8e..8ee3ebcb3 100644
--- a/projects/v3/src/app/services/unlock-indicator.service.ts
+++ b/projects/v3/src/app/services/unlock-indicator.service.ts
@@ -74,7 +74,7 @@ export class UnlockIndicatorService {
   /**
    * Clear all tasks related to a particular activity
    *
-   * @param   {number[]}        id  [id description]
+   * @param   {number[]}        id  can either be activityId or milestoneId
    *
    * @return  {UnlockedTask[]}      unlocked tasks that were cleared
    */
@@ -130,23 +130,6 @@ export class UnlockIndicatorService {
     return removedTask;
   }
 
-  dedupStored(records) {
-    const uniqueRecords = new Map();
-
-    records.forEach(record => {
-      // Determine the type of identifier and create a unique key
-      const key = `milestoneId:${record.milestoneId || 'none'}-activityId:${record.activityId || 'none'}-taskId:${record.taskId || 'none'}`;
-
-      // If the key doesn't exist in the map, add the record
-      if (!uniqueRecords.has(key)) {
-        uniqueRecords.set(key, record);
-      }
-    });
-
-    // Return an array of unique records
-    return Array.from(uniqueRecords.values());
-  }
-
   // Method to transform and deduplicate the data
   transformAndDeduplicateTodoItem(data) {
     const uniqueEntries = new Map();
diff --git a/serverless-appv3.yml b/serverless-appv3.yml
index 7dbd8f89b..68ac8425b 100644
--- a/serverless-appv3.yml
+++ b/serverless-appv3.yml
@@ -196,71 +196,71 @@ resources:
             - !GetAtt 'AppV2CloudFrontDistribution.DomainName'
 
 
-    HTTPCode4XXTooHighAlarm:
-      Condition: LiveServerOnly
-      Type: 'AWS::CloudWatch::Alarm'
-      Properties:
-        AlarmDescription: '${env:AppV3S3Bucket} - receives 4XX HTTP status codes from CDN'
-        Namespace: 'AWS/CloudFront'
-        MetricName: 4xxErrorRate
-        Statistic: Average
-        Period: 60
-        EvaluationPeriods: 3
-        ComparisonOperator: GreaterThanThreshold
-        Threshold: 3
-        AlarmActions:
-        - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
-        Dimensions:
-        - Name: Region
-          Value: Global
-        - Name: DistributionId
-          Value: !Ref AppV2CloudFrontDistribution
-        TreatMissingData: notBreaching
-        Unit: Percent
+    # HTTPCode4XXTooHighAlarm:
+    #   Condition: LiveServerOnly
+    #   Type: 'AWS::CloudWatch::Alarm'
+    #   Properties:
+    #     AlarmDescription: '${env:AppV3S3Bucket} - receives 4XX HTTP status codes from CDN'
+    #     Namespace: 'AWS/CloudFront'
+    #     MetricName: 4xxErrorRate
+    #     Statistic: Average
+    #     Period: 60
+    #     EvaluationPeriods: 3
+    #     ComparisonOperator: GreaterThanThreshold
+    #     Threshold: 3
+    #     AlarmActions:
+    #     - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
+    #     Dimensions:
+    #     - Name: Region
+    #       Value: Global
+    #     - Name: DistributionId
+    #       Value: !Ref AppV2CloudFrontDistribution
+    #     TreatMissingData: notBreaching
+    #     Unit: Percent
     
-    HTTPCode5XXTooHighAlarm:
-      Condition: LiveServerOnly
-      Type: 'AWS::CloudWatch::Alarm'
-      Properties:
-        AlarmDescription: '${env:AppV3S3Bucket} - receives 5XX HTTP status codes from CDN'
-        Namespace: 'AWS/CloudFront'
-        MetricName: 5xxErrorRate
-        Statistic: Average
-        Period: 60
-        EvaluationPeriods: 3
-        ComparisonOperator: GreaterThanThreshold
-        Threshold: 3
-        AlarmActions:
-        - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
-        Dimensions:
-        - Name: Region
-          Value: Global
-        - Name: DistributionId
-          Value: !Ref AppV2CloudFrontDistribution
-        TreatMissingData: notBreaching
-        Unit: Percent
+    # HTTPCode5XXTooHighAlarm:
+    #   Condition: LiveServerOnly
+    #   Type: 'AWS::CloudWatch::Alarm'
+    #   Properties:
+    #     AlarmDescription: '${env:AppV3S3Bucket} - receives 5XX HTTP status codes from CDN'
+    #     Namespace: 'AWS/CloudFront'
+    #     MetricName: 5xxErrorRate
+    #     Statistic: Average
+    #     Period: 60
+    #     EvaluationPeriods: 3
+    #     ComparisonOperator: GreaterThanThreshold
+    #     Threshold: 3
+    #     AlarmActions:
+    #     - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
+    #     Dimensions:
+    #     - Name: Region
+    #       Value: Global
+    #     - Name: DistributionId
+    #       Value: !Ref AppV2CloudFrontDistribution
+    #     TreatMissingData: notBreaching
+    #     Unit: Percent
 
-    HTTPCodeTotalErrorRateTooHighAlarm:
-      Condition: LiveServerOnly
-      Type: 'AWS::CloudWatch::Alarm'
-      Properties:
-        AlarmDescription: '${env:AppV3S3Bucket} - receives Total Error Rate HTTP status codes from CDN'
-        Namespace: 'AWS/CloudFront'
-        MetricName: TotalErrorRate
-        Statistic: Average
-        Period: 60
-        EvaluationPeriods: 3
-        ComparisonOperator: GreaterThanThreshold
-        Threshold: 3
-        AlarmActions:
-        - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
-        Dimensions:
-        - Name: Region
-          Value: Global
-        - Name: DistributionId
-          Value: !Ref AppV2CloudFrontDistribution
-        TreatMissingData: notBreaching
-        Unit: Percent
+    # HTTPCodeTotalErrorRateTooHighAlarm:
+    #   Condition: LiveServerOnly
+    #   Type: 'AWS::CloudWatch::Alarm'
+    #   Properties:
+    #     AlarmDescription: '${env:AppV3S3Bucket} - receives Total Error Rate HTTP status codes from CDN'
+    #     Namespace: 'AWS/CloudFront'
+    #     MetricName: TotalErrorRate
+    #     Statistic: Average
+    #     Period: 60
+    #     EvaluationPeriods: 3
+    #     ComparisonOperator: GreaterThanThreshold
+    #     Threshold: 3
+    #     AlarmActions:
+    #     - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
+    #     Dimensions:
+    #     - Name: Region
+    #       Value: Global
+    #     - Name: DistributionId
+    #       Value: !Ref AppV2CloudFrontDistribution
+    #     TreatMissingData: notBreaching
+    #     Unit: Percent
 
 
   # FILE storage Bucket 
diff --git a/serverless.yml b/serverless.yml
index f8d6ac228..b627987a0 100644
--- a/serverless.yml
+++ b/serverless.yml
@@ -193,71 +193,71 @@ resources:
             - !GetAtt 'AppV2CloudFrontDistribution.DomainName'
 
 
-    HTTPCode4XXTooHighAlarm:
-      Condition: LiveServerOnly
-      Type: 'AWS::CloudWatch::Alarm'
-      Properties:
-        AlarmDescription: '${env:APPV2S3BUCKET} - receives 4XX HTTP status codes from CDN'
-        Namespace: 'AWS/CloudFront'
-        MetricName: 4xxErrorRate
-        Statistic: Average
-        Period: 60
-        EvaluationPeriods: 3
-        ComparisonOperator: GreaterThanThreshold
-        Threshold: 3
-        AlarmActions:
-        - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
-        Dimensions:
-        - Name: Region
-          Value: Global
-        - Name: DistributionId
-          Value: !Ref AppV2CloudFrontDistribution
-        TreatMissingData: notBreaching
-        Unit: Percent
+    # HTTPCode4XXTooHighAlarm:
+    #   Condition: LiveServerOnly
+    #   Type: 'AWS::CloudWatch::Alarm'
+    #   Properties:
+    #     AlarmDescription: '${env:APPV2S3BUCKET} - receives 4XX HTTP status codes from CDN'
+    #     Namespace: 'AWS/CloudFront'
+    #     MetricName: 4xxErrorRate
+    #     Statistic: Average
+    #     Period: 60
+    #     EvaluationPeriods: 3
+    #     ComparisonOperator: GreaterThanThreshold
+    #     Threshold: 3
+    #     AlarmActions:
+    #     - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
+    #     Dimensions:
+    #     - Name: Region
+    #       Value: Global
+    #     - Name: DistributionId
+    #       Value: !Ref AppV2CloudFrontDistribution
+    #     TreatMissingData: notBreaching
+    #     Unit: Percent
     
-    HTTPCode5XXTooHighAlarm:
-      Condition: LiveServerOnly
-      Type: 'AWS::CloudWatch::Alarm'
-      Properties:
-        AlarmDescription: '${env:APPV2S3BUCKET} - receives 5XX HTTP status codes from CDN'
-        Namespace: 'AWS/CloudFront'
-        MetricName: 5xxErrorRate
-        Statistic: Average
-        Period: 60
-        EvaluationPeriods: 3
-        ComparisonOperator: GreaterThanThreshold
-        Threshold: 3
-        AlarmActions:
-        - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
-        Dimensions:
-        - Name: Region
-          Value: Global
-        - Name: DistributionId
-          Value: !Ref AppV2CloudFrontDistribution
-        TreatMissingData: notBreaching
-        Unit: Percent
+    # HTTPCode5XXTooHighAlarm:
+    #   Condition: LiveServerOnly
+    #   Type: 'AWS::CloudWatch::Alarm'
+    #   Properties:
+    #     AlarmDescription: '${env:APPV2S3BUCKET} - receives 5XX HTTP status codes from CDN'
+    #     Namespace: 'AWS/CloudFront'
+    #     MetricName: 5xxErrorRate
+    #     Statistic: Average
+    #     Period: 60
+    #     EvaluationPeriods: 3
+    #     ComparisonOperator: GreaterThanThreshold
+    #     Threshold: 3
+    #     AlarmActions:
+    #     - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
+    #     Dimensions:
+    #     - Name: Region
+    #       Value: Global
+    #     - Name: DistributionId
+    #       Value: !Ref AppV2CloudFrontDistribution
+    #     TreatMissingData: notBreaching
+    #     Unit: Percent
 
-    HTTPCodeTotalErrorRateTooHighAlarm:
-      Condition: LiveServerOnly
-      Type: 'AWS::CloudWatch::Alarm'
-      Properties:
-        AlarmDescription: '${env:APPV2S3BUCKET} - receives Total Error Rate HTTP status codes from CDN'
-        Namespace: 'AWS/CloudFront'
-        MetricName: TotalErrorRate
-        Statistic: Average
-        Period: 60
-        EvaluationPeriods: 3
-        ComparisonOperator: GreaterThanThreshold
-        Threshold: 3
-        AlarmActions:
-        - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
-        Dimensions:
-        - Name: Region
-          Value: Global
-        - Name: DistributionId
-          Value: !Ref AppV2CloudFrontDistribution
-        TreatMissingData: notBreaching
-        Unit: Percent
+    # HTTPCodeTotalErrorRateTooHighAlarm:
+    #   Condition: LiveServerOnly
+    #   Type: 'AWS::CloudWatch::Alarm'
+    #   Properties:
+    #     AlarmDescription: '${env:APPV2S3BUCKET} - receives Total Error Rate HTTP status codes from CDN'
+    #     Namespace: 'AWS/CloudFront'
+    #     MetricName: TotalErrorRate
+    #     Statistic: Average
+    #     Period: 60
+    #     EvaluationPeriods: 3
+    #     ComparisonOperator: GreaterThanThreshold
+    #     Threshold: 3
+    #     AlarmActions:
+    #     - {'Fn::ImportValue': '${env:STACK_NAME}-ChatBotSNSTopicARN-${env:ENV}'}
+    #     Dimensions:
+    #     - Name: Region
+    #       Value: Global
+    #     - Name: DistributionId
+    #       Value: !Ref AppV2CloudFrontDistribution
+    #     TreatMissingData: notBreaching
+    #     Unit: Percent
 
 
   # FILE storage Bucket