--- a/ForgeTracker/forgetracker/model/ticket.py
+++ b/ForgeTracker/forgetracker/model/ticket.py
@@ -79,7 +79,7 @@
     @property
     def not_closed_mongo_query(self):
         return dict(
-            status={'$in': self.open_status_names})
+            status={'$in': list(self.set_of_open_status_names)})
     
     @property
     def closed_query(self):