Changing Your Payment Method
You'll need to add the new card first and then delete the old card since you do have an auto-renewal subscription.
First, go to your Topaz Labs Account Page, and on the dashboard, you'll see "payment methods." Click on that tab.

Then click "Add Payment Method":

Enter the new information, and when the card is added, click "Make Default." After selecting the default card, you can delete the old card.

