On the app, you generally have a Rewards section that you can see your banked rewards dollars balance. From this, you can hit Redeem, or the equivalent based on your app, and a QR code will be generated. This QR code can be used at the POS but NOT on the app.
In order to apply the dollars on the app, you must go through the entire checkout process and in the end, your app will have the option to apply the banked reward dollars like below. When you generate the QR code and try to use this process, you may get an error like "Oops! This offer is not valid with this order."
If further assistance is required, submit a ticket to Punchh Support. (For help submitting a ticket, click here)