You can easily set a default payment card for your account by following these steps:
Log in to your account.
Click on View Wallet.
Click on the "Set Default" next to the card you wish to designate as the default payment method.
Please note that your default payment method will be the card charged at the time of your invoice due date.
If you would like to add a new card, click "Add Payment Method" and you will be prompted to fill out the card number, expiration date, CVC.
If you would like to remove your card, click Remove. Please note that if you have any unpaid invoices associated with your account, you will need to settle these before you can remove your card. Please ensure that all outstanding invoices are paid in full, and then you will be able to proceed with card removal.