First you need to download an IP changer.
Download asprate IP Changer here :-
OT Changer.net - Changes your Tibia experience! -> the rar one or zip doesnt matter.
Install , then run it and put a tick on the thing that is found >> of the IP Changer, after that put in the server IP and click "Change IP" , Then you can logon.
Also use the port the server is.. normally its 7171
P.S :- You must have your tibia client running
Rep++ Me if I helped!