If you open the app and you see an "Oops! Invalid Signature" error pop up on the screen this would be the result of lost internet connectivity.
What we recommend as a next step after you get the error would be to delete the app, check the internet connection and signal strength (make sure that the device is not connected to any open Wifi). Then download the app again and see if the issue persists.
If the issue persists please submit a ticket to punchh support at support.punchh.com by clicking on "Submit a Request" at the top of the page.
In the ticket please include the device details (Model name and OS version) of the device you are using.