If you want to make any changes to your buyback order before shipping us your books - add or delete a book, change quantities - please submit a new buyback order. Your original order will automatically expire after 7 days, so there is no need to cancel it. If you need to make any changes related to the method of payment, you can do this in your account at your Online Bookstore at any time before the books are received in our warehouse. After that, there is no option to change the payment method or information.