diff --git a/racketmq/hub/websocket.rkt b/racketmq/hub/websocket.rkt
index 13a8312..8038da7 100644
--- a/racketmq/hub/websocket.rkt
+++ b/racketmq/hub/websocket.rkt
@@ -46,6 +46,8 @@
 
            (assert (web-response-websocket id))
 
+           (stop-when (websocket-connection-closed id))
+
            (on (message ($ n (notification topic
                                            $canonical-hub
                                            $canonical-topic