I don't know if live chat is still in the game, but that would be your best bet. It was one thing back when it was one level. Ten seems like quite the stretch, but good luck.
Momentum matters, the faster you address the issue, the more of a chance you will have because it will seem like a genuine mistake.
So do not lock EXP on the toon or farm anything. You don't want them to get the idea of you being up to some potentially shady stuff.
While GM's usually act stupid, it's exactly that. An act. Most of them play the game too and they can do 2+2. It's simply faster to plead ignorance or "follow the book" and move on than have an actual discussion.
They leave notes for other GM's once they resolve a ticket issue and once you addressed the issue 10 times, you won't be able to appeal it again.
It also helps if you haven't had any requests within the last 6 months. They have some sort of "big favor" system where they are more inclined to do something big like this if you haven't had any other "big" problems in the past 6 months.