Sometimes, a customer may change their mind mid-way through the sale. In this case, you need to cancel the sale or start over. If you have not yet taken payment, click the Dismiss Sale button at the top of the payment box to clear it out.
If you have already taken a payment, you will need to complete the sale and issue return using the standard return process.
If you have accidentally continued the wrong Layby, or On Account sale, you can use the Dismiss Sale button to exit. The sale will not be deleted, and you can go back to it at any time.