If you don't have the email address I doubt they'll let you change the password (and therefore obtain access) based just on your word.
So you sold it to a friend and they sold it to someone else? Sounds like it isn't yours anymore anyway! If it's still in possession of your friend, why not ask them?
Badbear and Theymos are known for recovering hacked accounts, I haven't heard of anything regarding bought account. You can try your luck and sign a message from your own address, requesting for recovery of the account together with the signed message from that account proving the ownership transfer.
The OP never said the account was hacked!
I did not sell the account, rather I allowed him to use it while under my cobtrol.
Anyways, thanks for the input everyone. I'll contact an administrator about recovery, and if that doesn't work, I'll pm the current user of the account requesting a payment for the account. If they decline, I'll just leak the account name as being traded around and switching ownership and it will lose its value.
Your best bet would be to go to your friend that used it whall under your control. I'm not sure if they will recover it for you unless you prove a lot email, staked address, etc.
In one part you mention you allowed friend to use account. In another you mention you will contact current user asking for payment, which sounds like it's not in friends control.
If it transferred from your friend to another I have a feeling you are going to have a hard time getting it back unless you have some concrete evidence showing you loaned it to friend. And then need to say more about story on how this 3rd user got it. Just is a lot for staff to investigate.
