diff --git a/apps/opm/services.py b/apps/opm/services.py
index cc798a51..8650a583 100644
--- a/apps/opm/services.py
+++ b/apps/opm/services.py
@@ -123,9 +123,11 @@ def close_mtask(opl: Opl):
     """
     from celery.app.control import Control
     from server.celery import app
+    celery_control = Control(app=app)
+    if opl.mtask_uid:
+        celery_control.revoke(opl.mtask_uid, terminate=True)
     qs = TaskResult.objects.filter(task_args__contains=opl.id, status__in=['PENDING', 'RECEIVED', 'STARTED'])
     if qs:
-        celery_control = Control(app=app)
         for i in qs:
             celery_control.revoke(i.task_id, terminate=True)
     opl.mtask_uid = None