diff --git a/FAQ.md b/FAQ.md
index 610841f..961523c 100644
--- a/FAQ.md
+++ b/FAQ.md
@@ -417,6 +417,8 @@ https://github.com/rustdesk/rustdesk/issues/388#issuecomment-1915892570
 
 Case study: 
 
+- Case 1
+
 > A: What happened lately?
 
 > B: Nothing, our rustdesk works since 8 months. But this morning it’s doesn’t work, even after restarting the docker.
@@ -425,6 +427,15 @@ Case study:
 
 > B: Thanks, you have the true answer. The issue come from our Fortinet Client.
 
+- Case 2
+
+The controlled side works fine with UDP `21116` port, but it can not connect to the `hbbs` server with TCP `21116 port.
+
+![image](https://github.com/user-attachments/assets/db2be786-89e3-4a2a-9702-d511fa453feb)
+
+
+
+
 # Command line
 
 https://github.com/rustdesk/rustdesk/discussions/3980#discussioncomment-11172341