I got a used iPhone 4S off eBay today. It was both unlocked and jailbroken and I am currently running it on t-mobile. I'm trying to set up iMessage on it, but every time I try to, it asks for the password of the person who had the phone before me. Is there anyway to prevent this and just have it sign in with my Apple ID instead? I have the same problem with Facetime. Can I fix this, or do I need to somehow get the password from the person who had the phone before me?