diff --git a/packages/rmb_direct_client/lib/client.ts b/packages/rmb_direct_client/lib/client.ts
index b85aeb0c33..e1bbc62006 100644
--- a/packages/rmb_direct_client/lib/client.ts
+++ b/packages/rmb_direct_client/lib/client.ts
@@ -313,6 +313,8 @@ class Client {
         } else {
           clientEnvelope.plain = new Uint8Array(Buffer.from(requestData));
         }
+      } else {
+        clientEnvelope.plain = new Uint8Array();
       }
 
       clientEnvelope.relays = this.twin.relay.split("_");