Good luck getting your account back! To parrot what everyone else is saying, I've had luck when bugging them on social media. Twitter specifically in my case.
When making tickets I give them literally every bit of information I know. Email, DOB, Pins, pets on the account, neofriends, neomails, items, nc purchases. If you have any of those emails you get when winning the lottery too I put those in there.
I always make up some story about how I went on a haitus and I wasn't able to log in when I came back. Usually I get an answer saying my account is frozen, and then I just act really confused and scared. It's all about playing dumb imo. I've gotten 2 accounts unfrozen this way.