If you're experiencing an issue with the latest update of an app where it only works in portrait mode on your iPad Pro 11" (1st generation) running iPadOS 15.1, there are a few steps you can try to resolve the issue:
Check for App Updates: Make sure you have the latest version of the app installed. Sometimes developers release updates specifically to address compatibility issues with new operating system versions. Open the App Store and go to the "Updates" tab to check for any available updates for the app in question. Dave The Diver
Check for App Updates: Make sure you have the latest version of the app installed. Sometimes developers release updates specifically to address compatibility issues with new operating system versions. Open the App Store and go to the "Updates" tab to check for any available updates for the app in question. Dave The Diver