diff --git a/app/demo.py b/app/demo.py
index fd601df..c245728 100644
--- a/app/demo.py
+++ b/app/demo.py
@@ -115,7 +115,7 @@ def send_group_message(message_id, content):
         ReplyMessageRequest.builder()
         .request_body(
             ReplyMessageRequestBody.builder()
-            .content(json.djumps(content))
+            .content(json.dumps(content))
             .msg_type("text")
             .reply_in_thread(True)
             .uuid(message_id)