To adjust a transaction performed on the current day:  

1. Access the desired ticket.
2. At the bottom of the Ticket Preview panel, select the submitted payment that you want to adjust. In this example, Custom Tender is the selected payment. When you select a payment, the POS displays the Tip, Print, and Void Payment buttons.
   
3. To add or change the tip amount, select Tip, and then enter a new amount in the keypad.