Resolve review

Author: phanthaiduong22

articles/azure-web-pubsub/reference-protobuf-webpubsub-subprotocol.md

@@ -168,10 +168,6 @@ The sender's `dataType` will cause one of the following messages to be sent:
 
 The Web PubSub service can also send system-related responses to the client.
 
-### Pong response
-
-The Web PubSub service sends a `PongMessage` to the client when it receives a `PingMessage` from the client.
-
 #### Connected
 
 When the client connects to the service, you receive a `DownstreamMessage.SystemMessage.ConnectedMessage` message.
@@ -180,6 +176,10 @@ When the client connects to the service, you receive a `DownstreamMessage.System
 
 When the server closes the connection or the service declines the client, you receive a `DownstreamMessage.SystemMessage.DisconnectedMessage` message.
 
+### Pong response
+
+The Web PubSub service sends a `PongMessage` to the client when it receives a `PingMessage` from the client.
+
 ## Next steps
 
 [!INCLUDE [next step](includes/include-next-step.md)]