Ok, this is what you would need to have set if you didn't already
+set dedicated +map <mapname>
Then, you need to check your server.cfg file for this line: (line #9)
set public 0 // set to 0 if you don't want this on the public server list
Setting this to "1" will send a heartbeat to the server lists.
Make sure you only have "set public" once in the config file.