diff --git a/app/demo.py b/app/demo.py
index aeecca4..e36b65d 100644
--- a/app/demo.py
+++ b/app/demo.py
@@ -39,7 +39,7 @@ def do_p2_im_message_receive_v1(data: P2ImMessageReceiveV1) -> None:
     content = json.loads(content)
     if message_type == "post":
         content = content["content"]
-        for item in chain.from_iterable(data):
+        for item in chain.from_iterable(content):
             if item.get("tag") == "text":
                 message_content += item["text"]