The options discussed on this page are found by selecting Menu --> Setup --> Till --> General

To set reasons against refunds, click to Menu - Setup - Till and choose Refund Reasons. The table below appears.

To enter a reason, click into a blank line and start typing. When a refund is processed on the Till (see How Do I Refund a Payment?), the user is asked to choose a reason. These can be reported on under Business Intelligence.