diff --git a/be/app/Http/Controllers/MasterTaskController.php b/be/app/Http/Controllers/MasterTaskController.php
index 8a6f62d..b385e13 100644
--- a/be/app/Http/Controllers/MasterTaskController.php
+++ b/be/app/Http/Controllers/MasterTaskController.php
@@ -151,7 +151,7 @@ class MasterTaskController extends Controller
         foreach ($mastertask->subtasks as $subtask) {
             if ($subtask->timesheets()->exists()) {
                 return response()->json([
-                    'message' => 'Cannot delete mastertask containing subtasks submitted timesheets.',
+                    'message' => 'Cannot delete mastertask containing subtasks with submitted timesheets.',
                 ], 400);
             }
         }
diff --git a/be/app/Http/Controllers/SubTaskController.php b/be/app/Http/Controllers/SubTaskController.php
index b496647..c0b16f2 100644
--- a/be/app/Http/Controllers/SubTaskController.php
+++ b/be/app/Http/Controllers/SubTaskController.php
@@ -162,6 +162,13 @@ class SubTaskController extends Controller
     {
         $subtask = SubTask::find($id);
 
+        // ak je Master task v stave ukončený, nedovolime update
+        if ($subtask->is_finished == 1) {
+            return response()->json([
+                'message' => 'Cannot update subtask with is_finished 1.',
+            ], 400);
+        }
+
         $validator = Validator::make($request->all(), [
             'data.employee_id' => 'required',
             'data.duration' => 'required',