Amazon account auto changed back to origial mail?

Yesterday, I bought 2 amazon accounts and already changed all thing to become my information. name , phone, address, set 2step.
But after i have refund and make order. it automatically changed back to the original mail. when i sign in with new mail it said this email does not link with any account.
i dont think the seller changed it. after changing all information, i tried signing in with old email and it also said that no account related with old email

what happend ? i just call amazon and they said that it will take 48-72 hours to investiagate.

i remember that some weeks ago, i also changed my own account to new email and use refund service. after getting refund and order, i can not access with new email but i can access with old email.

because 2 accounts i said above, i bought from internet, so i can not use old email to get new password.

some information for who want to use cracked account to refund.

any idea about that ?