diff --git a/cardano-api/internal/Cardano/Api/Eras/Core.hs b/cardano-api/internal/Cardano/Api/Eras/Core.hs
index f14bd50399..1a0cde248b 100644
--- a/cardano-api/internal/Cardano/Api/Eras/Core.hs
+++ b/cardano-api/internal/Cardano/Api/Eras/Core.hs
@@ -152,10 +152,10 @@ forEraMaybeEon :: ()
 forEraMaybeEon =
   inEonForEra Nothing Just
 
-maybeEon ::
-  ( Eon eon
-  , IsCardanoEra era      -- ^ Era to check
-  ) => Maybe (eon era)    -- ^ The eon if supported in the era
+maybeEon :: ()
+  => Eon eon
+  => IsCardanoEra era
+  => Maybe (eon era)  -- ^ The eon if supported in the era
 maybeEon =
   inEonForEra Nothing Just cardanoEra