diff --git a/FAQ.md b/FAQ.md
index 4fb9dfd..6a2f334 100644
--- a/FAQ.md
+++ b/FAQ.md
@@ -72,7 +72,7 @@ The hardware requirements are very low, the minimum configuration of the cloud s
 
 # Deploy RustDesk server in intranet.
 
-First you should set relay server with public ip explicitly on "settings" -> "relay" of web console. Or you can set relay server (public ip) explcitly on controlled side (remote side, the device you want to control).
+First you should set relay server with public ip (you need to fix NAT hairping problem to use public ip in intranet first) explicitly on "settings" -> "relay" of web console. Or you can set relay server (public ip) explcitly on controlled side (remote side, the device you want to control).
 
 Try [force relay](https://github.com/rustdesk/rustdesk/wiki/FAQ#force-relay) if you encounter connection problem.