This is what it gives me:
One of the following suggestions may help you:
Your server is currently offline.
GameTracker needs your server to be online before you can add it to our database. Please restart your server and make sure it's up before hitting ADD SERVER again.
You entered the wrong query port.
Please update your query port and hit scan again
Your server is firewalled.
Please turn off any firewall you have that may block scanning or whitelist the gametracker scanning IP addresses:
208.167.225.11
208.167.225.12
208.167.225.13
108.61.78.147
108.61.78.148
108.61.78.149
108.61.78.150


(My ip 203.219.212.237)
Join Port (27015)

Contact your server provider to open the port in the firewall. Thanks.

what do u mean by that?

GT cannot be blocked from scanning the server. It will be impossible to gather information about the server. GT needs to be able to scan it via the UDP protocol on that port.

Contact your game server provider for further assistance on this step if you do not know what you are doing.