diff --git a/app/services/clusters/create_service.rb b/app/services/clusters/create_service.rb
index 1d45df329c0..5a9da053780 100644
--- a/app/services/clusters/create_service.rb
+++ b/app/services/clusters/create_service.rb
@@ -38,6 +38,8 @@ module Clusters
         { cluster_type: :project_type, projects: [clusterable] }
       when ::Group
         { cluster_type: :group_type, groups: [clusterable] }
+      else
+        raise NotImplementedError
       end
     end