We are experiencing the same issue. @agkvein did you ever get any feedback from Apple?

Not working with any versions of Xcode, this is really not good 😅

It's the exact same thing I'm experiencing, but it's all the Xcode projects. I have tried to create new project and I get the same code signing error, I have tried existing projects it's the same. I think it's not related to the Xcode projects, but something in macOS 12 that does not comply correctly with the Xcode 12 application. I will try in Xcode 13 beta 1 now and see if that changes anything.