I’m having a problem entering my restore code, how can I fix it?
Did you set a security code? If not, try to leave the field empty.
The account does not have any security code configured and it says that the restoration code is incorrect 
Did you check on errors like mistaking 0 (zero) or O (letter o) or I (i) or l (L)?
If you cannot manage to restore your account, please contact support directly.
Provide your friend ID and your purchase receipt, possibly more data to prove it’s your own account.
I wish you best of luck that you can get your account back.