diff --git a/apps/wpm/models.py b/apps/wpm/models.py
index 02195c10..051a27ae 100644
--- a/apps/wpm/models.py
+++ b/apps/wpm/models.py
@@ -127,7 +127,7 @@ class WMaterial(CommonBDModel):
 
     @property
     def count_handovering(self): 
-        return  Handoverb.objects.filter(wm=self, submit_time__isnull=True).aggregate(count=Sum('count'))['count'] or 0
+        return  Handoverb.objects.filter(wm=self, handover__submit_time__isnull=True).aggregate(count=Sum('count'))['count'] or 0
 
     @classmethod
     def mat_in_qs(cls, mtask: Mtask, qs=None):