In order to update your credit card details securely stored on your GoFax account, your account does require a security verification to be performed. If you are unable to access the "Change My Credit Card" page of your secure GoFax web portal, you will see this message appear:
"Your account requires final verification from our team"
This may be due to your account missing some contact and address details. Please log in and update your account details under 'My Account' and then contact Support for further assistance.