To cancel a transaction and clear it from the Point of Sale screen, click the No Sale button, as shown below:
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Once you have clicked the No Sale button, you will see a prompt that asks you to confirm that wish to proceed with the No Sale:
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Clicking No will return you back to the transaction.
Clicking Yes will clear all items from the transaction, as well as the customer (if set). This presents you with a clear Point of Sale screen to begin your next transaction.
Clicking ‘No Sale’ on a customer order or quote
If you click ‘No Sale' with a Special Order, Layaway, Workshop Job or Quote recalled, the order will remain open but any changes you made since the recall will not be saved.