I got locked out of my Gmail for a few years because I moved internationally and Google decided it just didn't like my new ip. I had access to the recovery email and would even get, "someone attempted to sign in emails." But Google just wouldn't let me in at all. I contacted support and they were no help at all. I tried to vpn back to normal locations but at that point I was flagged or something. I would try every few months after I gave up. About 3 years later it just magically let me in and I got all my stuff back. Still have no actual idea why it happened.