well there seemed to be this custom that when you join you make an intro post showing a picture of yourself with the joining date to later be able to reclaim your account in the event it got stolen or you got locked out. there was something about other people vouching for you as well who know you on the platform, you'd have to dig a bit as I have never seen this play out anywhere I just know it used to be kind of a failsafe against situations like yours.