You must have Admin permission to delete a payment method
You must complete any open contract or settle any unsettled balance before you can delete a credit card in the following cases:
A payment method is linked to an open contract that is configured to charge for contract-related expenses
A finished contract with an unsettled balance
Steps to add/delete payment method
Click the Customers tab in the left navigation bar
Locate a customer by entering the customer’s name in the search bar in the Customers pane. You can also click either the left navigation arrow or the right navigation arrow on the bottom right to locate a customer
Click the Overview tab in the Customer Details pane
Locate the Payment Information tile and click Add Payment in the upper-right corner
This action will open a fly-in on the right side of the screen in which to add/delete a payment method
Input credit card details to add a new payment method and click Save
Navigate to the Card(s) on File section and click Delete Card to delete a payment method
Select the Allow Debit checkbox to accept a debit card as a method of payment