But what happen if the seller take back his account by proving the ownership of old address after sell the account to someone? Is it still possible right?
Please respond, I'm curious about this one.
No need to worry if the buyer have signed message from the seller when buying accounts, that would serve as proof of account transfer and he cant claim it back
better to change the address to one of your address and sign it again and reporting that you have bought the account(a bit too drastic but it's the only way to avoid trouble afterward), because you never know with who you're dealing with