With WooCommerce 3.6, there were changes made to the refund workflow. The change was made to help shop owners to keep accurate tax records. It can be a bit confusing if you were used to entering an amount directly. Let’s walk through how refunds now work in WooCommerce.
1. Edit an order and click the refund button in the order details.
2. Use the quantity field next to the item you’re refunding to set the price or enter a price directly into the total field for that product.
3. Enter a shipping amount (optional)
4. Enter a reason for the refund and click the refund button for your payment gateway. There is also a checkbox you can use to restock items that are being refunded. That’s handy so you don’t have to manually adjust the stock level on the product after the refund.
That’s it. The “Refund amount” field will add up the amounts that you’ve entered into the fields above. It’s not directly editable as it used to be, but you can still select exactly how much to refund by entering in your information next to each product or shipping method.