Credit card payments can be refunded to your customer from the job details page.
Scroll to the bottom of the page and click on "REFUND" and enter the dollar amount to be refunded. You can choose to enter the full payment amount or a partial amount to be refunded. Click "ISSUE REFUND" to process, it may take up to 3-5 business before your customer sees refund in their account.
Pro Tip: If you are connected to Quickbooks, this refund will auto-reconcile, just as all of your credit card transactions do.