You can block a specific card number from transactions directly in your Dashboard or using the Stripe API.
There are two ways to block a card number in the Dashboard:
From the Payments section of your dashboard, click on the charge from the customer whose card you want to block, click Refund in the top right corner, and select Fraudulent ad the refund reason. This will automatically add the payment’s card and email to your blocklist.
You can block a card in the API two ways: