My friend had a problem, his account was suspended and after he contacted the support that answered this way:
“At this time, we have reviewed your account and have decided to release the account to you. The serial code has been permanently disabled as a result of the purchase using a fraudulent credit or debit card or stolen PayPal account.
In order to regain access to the game, you must re-purchase Guild Wars 2 again and apply a new, valid code to your account. To ensure this does not happen in the future, please purchase the game from one of our authorized retail partners https://buy.guildwars2.com/retailers or purchase directly from our website https://buy.guildwars2.com/. "
The question is: how can he use a new serial code with that account?