Making a refund to a gift card on Shopify POS
If a customer used a gift card to make a purchase and then wants to return the item for a refund, then you can make the refund to the same gift card and its balance is updated automatically.
Refund an order to a gift card with Shopify POS
To refund an order that was paid by gift card:
From the Shopify POS Orders screen, tap the order that was paid for with a gift card.
-beside each product to enter the quantity that you're refunding.
If the order shows that the customer paid for shipping, then tap Add to include the shipping cost in the refund.
Optional: Enter a reason for the refund.
When the refund is successful, tap Done to return to the order details screen.