diff --git a/apps/wpm/models.py b/apps/wpm/models.py
index d99c5a35..7765d8e7 100644
--- a/apps/wpm/models.py
+++ b/apps/wpm/models.py
@@ -128,7 +128,7 @@ class WMaterial(CommonBDModel):
 
     @property
     def count_working(self):
-        return Mlogb.objects.filter(wm_in=self, submit_time__isnull=True).aggregate(count=Sum('count_use'))['count'] or 0
+        return Mlogb.objects.filter(wm_in=self, mlog__submit_time__isnull=True).aggregate(count=Sum('count_use'))['count'] or 0
 
     @classmethod
     def mat_in_qs(cls, mtask: Mtask, qs=None):