diff --git a/website/client/src/components/group-plans/taskInformation.vue b/website/client/src/components/group-plans/taskInformation.vue
index ccc79a9198..db197c1d8b 100644
--- a/website/client/src/components/group-plans/taskInformation.vue
+++ b/website/client/src/components/group-plans/taskInformation.vue
@@ -222,6 +222,7 @@ export default {
 
     this.$root.$on('habitica:team-sync', () => {
       this.loadTasks();
+      this.loadGroupCompletedTodos();
     });
   },
   methods: {
diff --git a/website/client/src/components/tasks/task.vue b/website/client/src/components/tasks/task.vue
index becdd85e9f..1b59fb4600 100644
--- a/website/client/src/components/tasks/task.vue
+++ b/website/client/src/components/tasks/task.vue
@@ -1046,9 +1046,13 @@ export default {
     showTaskLockIcon () {
       if (this.isUser) return false;
       if (this.isGroupTask) {
-        if (this.isOpenTask) return false;
+        if (this.teamManagerAccess) return false;
+        if (this.isOpenTask) {
+          if (!this.task.completed) return false;
+          if (this.task.group.completedBy === this.user._id) return false;
+          return true;
+        }
         if (this.task.group.assignedUsers.indexOf(this.user._id) !== -1) return false;
-        if (this.teamManagerAccess && this.task.completed) return false;
       }
       return true;
     },
diff --git a/website/client/src/mixins/scoreTask.js b/website/client/src/mixins/scoreTask.js
index 91cf72ea4d..c1622cb395 100644
--- a/website/client/src/mixins/scoreTask.js
+++ b/website/client/src/mixins/scoreTask.js
@@ -56,11 +56,15 @@ export default {
       const canScoreTask = await this.beforeTaskScore(task);
       if (!canScoreTask) return;
 
-      try {
-        scoreTask({ task, user, direction });
-      } catch (err) {
-        this.text(err.message);
-        return;
+      if (direction === 'down' && task.group.completedBy && task.group.completedBy !== user._id) {
+        task.completed = false;
+      } else {
+        try {
+          scoreTask({ task, user, direction });
+        } catch (err) {
+          this.text(err.message);
+          return;
+        }
       }
 
       this.playTaskScoreSound(task, direction);
diff --git a/website/server/libs/tasks/index.js b/website/server/libs/tasks/index.js
index 793f4087a1..8bff8f98f7 100644
--- a/website/server/libs/tasks/index.js
+++ b/website/server/libs/tasks/index.js
@@ -8,6 +8,7 @@ import {
 } from './utils';
 import { model as Challenge } from '../../models/challenge';
 import { model as Group } from '../../models/group';
+import { model as User } from '../../models/user';
 import * as Tasks from '../../models/task';
 import apiError from '../apiError';
 import {
@@ -350,9 +351,34 @@ async function scoreTask (user, task, direction, req, res) {
   }
 
   const wasCompleted = task.completed;
-
   const firstTask = !user.achievements.completedTask;
-  const [delta] = shared.ops.scoreTask({ task, user, direction }, req, res.analytics);
+  let delta;
+  let rollbackUser;
+
+  if (
+    task.group.id && !task.userId
+    && direction === 'down'
+    && ['todo', 'daily'].includes(task.type)
+    && task.completed
+    && task.group.completedBy !== user._id
+  ) {
+    const group = await Group.getGroup({
+      user,
+      groupId: task.group.id,
+      fields: 'leader managers',
+    });
+    if (group.leader !== user._id && !group.managers[user._id]) {
+      throw new BadRequest('Cannot uncheck task you did not complete if not a manager.');
+    }
+    rollbackUser = await User.findOne({ _id: task.group.completedBy });
+  }
+
+  if (rollbackUser) {
+    delta = shared.ops.scoreTask({ task, user: rollbackUser, direction }, req, res.analytics);
+    await rollbackUser.save();
+  } else {
+    delta = shared.ops.scoreTask({ task, user, direction }, req, res.analytics);
+  }
   // Drop system (don't run on the client,
   // as it would only be discarded since ops are sent to the API, not the results)
   if (direction === 'up' && !firstTask) shared.fns.randomDrop(user, { task, delta }, req, res.analytics);