@GloomyFruitCake To protect yourself from behing hacked i would say
1: Use a good and strong password
2: Use Two-factor authentication (2FA) on all your accounts/emails to make sure your account stays protected.
When it comes to the ban part please read this:
https://help.ea.com/en/help/account/information-about-banned-or-suspended-accounts/Keep in mind that they can take sometime to answer and sometimes up to 2 weeks according to some players.
Hope this gives you answers to your questions and please notice that we can't help you with your case nor do anything related to your ban appeal.
So only thing to do is wait for a respons.