Why would you want to re-install it back to Wallet, did it ever work? I have never seen it work. Have always had to use the bar code in the App itself. I just finished writing to Supervalu, the owners of Cub Food. My letter was not a friendly one. I clearly pointed out there lies, and even sent screen shots of what they claim on the App store. The mere fact that on the Wallet portion of the App, it tells the cashier to type in the numbers, if the card can't be scanned. Should tell people that they knew before they released the App that it wasn't going to work, or may not work. Should tell you enough.
At least the App was free, maybe that is why Apple has let them get away with it.