For Punchh developed mobile apps, often the "Need Help" screen of the app will have options for App Feedback and Restaurant Feedback:
When a guest presses either of these buttons it will open a draft email on the guest's device with a recipient email address which is set in the Punchh Dashboard.
This email address can be found by going to Whitelabel -> Mobile Configuration, then scroll down to Extended Settings. It will be the first field there titled Support Email:
Once the email has been changed and applied by pressing Update at the bottom, the changes should update in the app within a few minutes.
If further assistance is required, submit a ticket to Punchh Support. (For help submitting a ticket, click here)