First, remove your existing stored payment details by following the three steps:
Navigate to the Account dropdown.
Choose Billing from the list and then Payment Details from the left hand menu.
Click Remove Payment Details.
You will then receive a payment reminder for the next invoice raised on your account at which time you can manually pay the invoice from the Billing section and register your new payment details.
Navigate to the Account drop down menu.
Choose Billing from the list.
Click Actions and then Pay on the invoice you would like to pay.