To process a refund, first select the payment app located at the upper right-hand side of the screen. Then, click on the "Transaction" tab. The app will prompt you to enter a 4-digit PIN number.

Once you're in, you can select the "History" option, where you'll find a "Refund" button on the left-hand side of the screen. Tap it, and you'll be given the option to provide a full or partial refund.

After selecting the refund amount, the app will ask if the customer would like a receipt. If they do, you can choose "yes" and the terminal will print out a copy for them first, followed by a copy for you. However, if the customer doesn't need a receipt, simply choose "no," and the terminal will print only one copy for you.