fix edge case

catalog/common/sites.py

@@ -163,7 +163,10 @@ class AbstractSite:
 
     @classmethod
     def match_or_create_item_for_resource(cls, resource):
+        try:
             previous_item = resource.item
+        except Item.DoesNotExist:
+            previous_item = None
         resource.item = cls.match_existing_item_for_resource(resource) or previous_item
         if resource.item is None:
             model = resource.get_item_model(cls.DEFAULT_MODEL)