diff --git a/strawberry_django/utils/inspect.py b/strawberry_django/utils/inspect.py
index 1860d4f3..998d1a22 100644
--- a/strawberry_django/utils/inspect.py
+++ b/strawberry_django/utils/inspect.py
@@ -217,7 +217,7 @@ def merge_selections(f1: SelectedField, f2: SelectedField) -> SelectedField:
                 else:
                     ret[f_name] = f
         else:  # pragma:nocover
-            assert_never(s)
+            raise TypeError(s)
 
     return ret