Press the "Order Lookup" button at the bottom of the scan screen. In the following screen you can search for the customer's order using their name, email, or order number if they have their receipt. From there you can redeem their tickets. BE CAREFUL:  Select specific tickets to redeem or redeem ALL tickets from this specific order. The number of redepmtions displayed is how many times that ticket has been redeemed in the past. "0" indicates it's available for redemption.