If your account has been compromised then this means that your login credentials have been made available and your account is either being used, or has been used, by another individual. You have been banned so that your account cannot be used by other people that wish to hack on the server without consequence.
To get unbanned:
-Change your email address password
-Change your Minecraft password at Mojang.com [Do not use the same password as your email]
-Appeal at appeals.ccgn.co and explain the issue, as well as that you have changed your passwords
To avoid this happening in future:
-Do not put your login credentials anywhere other than the Minecraft client launcher
-Do not log into websites using the same credentials as your Minecraft account (Especially Minecraft-related websites)
-Ensure that your password is unique and cannot be easily guessed
-Do not tell anybody else what your login credentials are, even if they claim to have a good reason for asking for them
Remember: We do not give out free ranks outside of the official forum and Twitter page, nor do we advertise rank giveaways in-game. Anybody in-game that claims to know how you can get a free rank is lying and is also likely a chat bot. If you see a player advertising free ranks, report them via the forums and they will be punished.
Seeing as you have been banned for the same reason three times now, my guess is that either your email has been hijacked and is being used to recover your account, or you have given out your login credentials after regaining access to your account. I would advise changing the password to your email, and ensuring that you follow the above guidelines. If your account is banned again then please inform me via the forums and I will look into the issue.