Which barcode do I scan?

You have to scan the barcodes of the item/s you have purchased only. Scanning the barcodes on the receipts does not give us the correct information about your purchases. There's also a chance the Scan n Go app will not pick up the receipt's barcode at all or register the scan, which will cause you to miss out on your weekly points. 

You should use the Scan n Go app in the same way you would use a self-checkout machine at your local grocery shop.