How to get get account back?

My Xbox account of 12 years was recently hacked and then locked. Xbox support has been no help in recovering my account. I’ve tried the recovery form multiple times but keep getting denied instantly. Every time I get support to call me they tell me the same thing, retry with as much info as you can. That’s what I’m doing but I get denied not even 5 minutes after submitting. I’m losing thousands of dollars worth of games because of this and to be honest my will to even play Xbox anymore. I’ve never had a problem before until now. If I could get into contact with some kind of supervisor to get this figured out that would be great, but if not there goes a customer for y’all.

:)