diff --git a/compiler/types/FamInstEnv.lhs b/compiler/types/FamInstEnv.lhs
index 0421f48a58bef36728299758a090d507e43ebfdf..50ced7d323e89544937172b77dec469b7d6ec8c8 100644
--- a/compiler/types/FamInstEnv.lhs
+++ b/compiler/types/FamInstEnv.lhs
@@ -959,9 +959,9 @@ normaliseTcApp env role tc tys
 
   | otherwise   -- No unique matching family instance exists;
                 -- we do not do anything
-  = (Refl role ty, ty)
-  where
-    ty = mkTyConApp tc tys
+  = let (co, ntys) = normaliseTcArgs env role tc tys in
+    (co, mkTyConApp tc ntys)
+    
 
 ---------------
 normaliseTcArgs :: FamInstEnvs            -- environment with family instances