(If this is for SA:MP)Well I know this has happened to me before. I got it fixed but I can't remember how I did it. Try rebooting your computer. If that doesn't work, go into your GTA San Andreas User Files folder and delete the file "gta_sa.set". If that still doesn't work, then try reinstalling SA:MP. Perhaps you can also try reseting your ip. It may be conflicting with the server somehow. I have no idea exactly what your problem is so there is no way I can tell how to fix it. ALSO, make sure the mods you have are not conflicting somehow with SA:MP.