Returns, exchanges and voids.

Sales history: find the sale by its receipt number or the customer, then choose Refund. Pick the items, whether they go back on the shelf, and how the money goes back.

An exchange is a refund and a new sale: the difference is paid or given back.

Void cancels a whole sale on the same day (it may need a manager's PIN).

Settings, Selling rules sets the return window and exchange-only returns.