The Inspection Support Network allows each ISN owner the ability to update their credit card for billing purposes!
Navigate to Administration -- ISN Invoices and Credit Card Information. Click on Update Credit Card.
Be sure you add the correct Billing Address for your credit card then click on Update Credit Card
You'll notice this page also provides each months total ISN invoices as well as a detailed accounting breakdown of what you are being billed for by clicking on the View tab beside each months total.