Google play says: “You need to use a different package name” - why?

Question

I have already published an app called com.mycompany.mygame on google play.

I then decided to publish an ad free version of it. I did not change the package name in

Answer 1

Apart from correcting app name in the Manifest I also had to change applicationId in the app's gradle.build file.

 defaultConfig {
    applicationId "com.example.changednameofmyapp"
    ...
}

Also, if you're using ProGuard, do not forget to change appropriate rules in your proguard-rules.pro

Just search the old package name in the whole project and change it.