To link a card to your account, go to the Billing
menu and open the 'Payment Methods' panel. Now click the 'Add' button. Enter your card details in the form. After saving the changes, $1 will be debited from your card to verify your card information. After verification that amount will be re-deposited to your card.
You can add multiple cards to your account, with only one of them acting as a primary card. When withdrawing a subscription payment, our billing system will try to use your primary card to make the payment. In case the payment fails, the system will attempt to withdraw money from other cards in the order you have them in your cards list, until the payment is successful.