diff --git a/seminar/migrations/0095_fix_polymorphism.py b/seminar/migrations/0095_fix_polymorphism.py
index cba9bda1..c8fca6f4 100644
--- a/seminar/migrations/0095_fix_polymorphism.py
+++ b/seminar/migrations/0095_fix_polymorphism.py
@@ -12,7 +12,7 @@ def fix_all(apps, schema_editor):
 			]:
 		Model = apps.get_model('seminar', modelname)
 		ct = ContentType.objects.get_for_model(Model)
-		Model.objects.update(polymorphic_ctype_id=ct)
+		Model.objects.update(polymorphic_ctype=ct)
 
 class Migration(migrations.Migration):