diff --git a/src/Simplex/Messaging/Protocol.hs b/src/Simplex/Messaging/Protocol.hs
index 679f077b7..122246868 100644
--- a/src/Simplex/Messaging/Protocol.hs
+++ b/src/Simplex/Messaging/Protocol.hs
@@ -1818,9 +1818,9 @@ tDecodeParseValidate THandleParams {sessionId, thVersion = v, implySessId} = \ca
 
 $(J.deriveJSON defaultJSON ''MsgFlags)
 
-$(J.deriveJSON (taggedObjectJSON id) ''CommandError)
+$(J.deriveJSON (sumTypeJSON id) ''CommandError)
 
-$(J.deriveJSON (taggedObjectJSON id) ''BrokerErrorType)
+$(J.deriveJSON (sumTypeJSON id) ''BrokerErrorType)
 
 $(J.deriveJSON defaultJSON ''BlockingInfo)