Ok so I joined yesterday, but when I joined I had a different ip to what I have now, is there anyway to reset or change this? Coz otherwise I can't connect to the server

Your IP address is only used to whitelist your GUID once this has happened you can login from any IP address.

If you are still being kicked by the whitelister make sure you login to the forums from the pc you are playing on and try and rejoin. Sometimes it can take a few minutes to sync up so if you get kicked retry a couple of times.

You need to make sure the in game name in your forum profile EXACTLY matches your name in game in DayZ also.