diff --git a/packages/extension-koni-ui/src/Popup/Home/Mission/TaskItem.tsx b/packages/extension-koni-ui/src/Popup/Home/Mission/TaskItem.tsx
index 31635b7a8fd..6382733f3b1 100644
--- a/packages/extension-koni-ui/src/Popup/Home/Mission/TaskItem.tsx
+++ b/packages/extension-koni-ui/src/Popup/Home/Mission/TaskItem.tsx
@@ -39,8 +39,8 @@ const _TaskItem = ({ actionReloadPoint, className, openWidget, reloadTask, task
   useEffect(() => {
     if (checking && reloadTask > 0) {
       apiSDK.completeTask(task.id)
-        .then((data: boolean) => {
-          if (data) {
+        .then((data: { completed: boolean, isSubmitting: boolean }) => {
+          if (data.completed) {
             setCompleted(true);
             setChecking(false);
             actionReloadPoint();
@@ -83,6 +83,29 @@ const _TaskItem = ({ actionReloadPoint, className, openWidget, reloadTask, task
         const date = `${now.getFullYear()}-${now.getMonth() + 1}-${now.getDate()}`;
         const data = JSON.stringify({ address, type: onChainType, date });
 
+        const checkCompleted = await apiSDK.completeTask(taskId);
+
+        if (checkCompleted) {
+          if (checkCompleted.completed) {
+            setCompleted(checkCompleted.completed);
+            setTaskLoading(false);
+
+            return;
+          }
+
+          if (checkCompleted.isSubmitting) {
+            setCompleted(false);
+            setTaskLoading(false);
+
+            notify({
+              message: t('Mission in progress on another device. Use one device to complete it.'),
+              type: 'warning'
+            });
+
+            return;
+          }
+        }
+
         res = await actionTaskOnChain(onChainType, networkKey, address, data);
 
         if ((res && res.errors.length > 0) || !res) {
diff --git a/packages/extension-koni-ui/src/connector/booka/sdk.ts b/packages/extension-koni-ui/src/connector/booka/sdk.ts
index 4dd33f894d6..04293aa794b 100644
--- a/packages/extension-koni-ui/src/connector/booka/sdk.ts
+++ b/packages/extension-koni-ui/src/connector/booka/sdk.ts
@@ -272,7 +272,7 @@ export class BookaSdk {
   }
 
   async completeTask (taskId: number | undefined) {
-    const taskHistoryCheck = await this.postRequest<{ completed: boolean }>(`${GAME_API_HOST}/api/task/check-complete-task`, { taskId });
+    const taskHistoryCheck = await this.postRequest<{ completed: boolean, isSubmitting: boolean }>(`${GAME_API_HOST}/api/task/check-complete-task`, { taskId });
 
     if (taskHistoryCheck && taskHistoryCheck.completed) {
       await this.fetchTaskCategoryList();
@@ -280,11 +280,9 @@ export class BookaSdk {
       await this.fetchTaskList();
 
       await this.reloadAccount();
-
-      return true;
     }
 
-    return false;
+    return taskHistoryCheck;
   }
 
   async finishTask (taskId: number, extrinsicHash: string, network: string) {