diff --git a/antarest/study/storage/variantstudy/variant_study_service.py b/antarest/study/storage/variantstudy/variant_study_service.py
index 8737824696..beb39c6d29 100644
--- a/antarest/study/storage/variantstudy/variant_study_service.py
+++ b/antarest/study/storage/variantstudy/variant_study_service.py
@@ -1082,7 +1082,7 @@ def clear_all_snapshots(self, retention_hours: timedelta, params: t.Optional[Req
             snapshot_clearing_task_instance,
             task_name,
             task_type=TaskType.SNAPSHOT_CLEARING,
-            ref_id="SNAPSHOT_CLEANING",
+            ref_id=None,
             custom_event_messages=None,
             request_params=params,
         )