diff --git a/openapi_message.go b/openapi_message.go
index e5e4b7f..8c66871 100644
--- a/openapi_message.go
+++ b/openapi_message.go
@@ -65,7 +65,6 @@ func (m *Message) String() string {
 			sb.WriteString(", URL: ")
 			sb.WriteString(u)
 		}
-		sb.WriteString(", URL: ")
 		return sb.String()
 	}
 	if m.SeqInChannel != "" {