Oh no! It sounds like you may have signed up using someone else's referral link. That's too bad. :(
Unfortunately, we cannot undo this for you and the Cash Back bonuses will remain as they are.
Helpful hint: If you're feeling bad about it, why don't you try referring someone else to Checkout 51 on your friend's behalf? Get them to sign-up with the link you originally wanted to use and make it up to them. :)