Hi,
You will need to check your manifest files ( there are probably 2 or 3, can be more)
Search for AndroidManifest in your project folder.
in those files you will have 1 or more of the same elements (@android:name=...)
but with different settings, make sure the settings are the same and only called on 1 AndroidManifest.
If you google : commandinvokationfailure : unable to merge android manifests
You will find some unity answers that solves the issue, it can be that you targetSdkVersion differs or some other settings are different.