Step 2: Open Payment Method Settings

To handle instant rebates correctly, you must create and use a dedicated payment method called Instant Rebate.
Go to your POS Settings menu.
In Settings, search for Payment Method.
Open the Payment Method configuration section.
Create a new payment method.
Name this payment method Instant Rebate (or a clear equivalent).
You should now see the newly created Instant Rebate payment method listed.
Confirm that the Instant Rebate payment method is active and available for use.