Garry's mod server problem

Hello.

I have a gmod server, this server is run on server machine in Germany and i and one friend can’t see the server in browse menu/favorites and anywhere but my friends see the server and they can join to server. only one friend and me can’t see it… also my Hlsw cant join to server. only i can see the server game-monitor or any server browser…

Edit:
i made image for this : http://imageshack.us/photo/my-images/836/77027552.jpg/

Server ip : 5.104.108.238:28922
Server name : [HUN/GER]Garry’s Mod BUILD Server @Random