diff --git a/core/admin.py b/core/admin.py
index c74cbd0c..92f57f51 100644
--- a/core/admin.py
+++ b/core/admin.py
@@ -49,15 +49,13 @@ class RelatedAutocompleteFilter(FieldListFilter):
         self.field_path = field_path
 
         self.lookup_kwarg = f"{field_path}__{field.target_field.name}__exact"
-        self.lookup_val = params.get(self.lookup_kwarg)
+        self.lookup_val = params.get(self.lookup_kwarg, "")
 
-        rel_model = field.remote_field.model
-        app_label = rel_model._meta.app_label
-        model_name = rel_model._meta.model_name
-        url_name = f"admin:{app_label}_{model_name}_autocomplete"
+        opts = model_admin.model._meta
+        url_name = f"admin:{opts.app_label}_{opts.model_name}_autocomplete"
         self.autocomplete_url = (
             reverse(url_name)
-            + f"?field_name={field.name}&limit={self.limit}"
+            + f"?field_name={field_path}&limit={self.limit}"
         )
 
     def expected_parameters(self):
@@ -76,7 +74,7 @@ class RelatedAutocompleteFilter(FieldListFilter):
             "display": _("—"),
             "autocomplete_url": self.autocomplete_url,
             "lookup_kwarg": self.lookup_kwarg,
-            "lookup_val": self.lookup_val or "",
+            "lookup_val": self.lookup_val,
         }