There are a few easy ways to refund a payment to any guest staying at your hotel.
Open the booking details screen by clicking on the relevant booking on the Monthly Room screen and selecting 
On the Payment (Return) screen, you can select the service or product related to the payment or you can perform the refund process by adding only the refund method, payment date, total amount and description.
You can also access the details of the reservation for which you will make a payment (return) from the homepage, monthly view or reservation list pages.