Just a beginner question. We are having an issue with our custom app (for our checkout custom discount code). The app is hosted via fly.io. It has been updated to the latest version of the Shopify API, but I want to revert it to a working version.
Note: I also don't know how to edit the app, as I did not create it. We no longer have contact with the old developer. I am new to app development, so I appreciate your help.
