Unity C# AndroidManifest landscape screen

Hey Guys! I am really new in Unity Android Developing, so I think my Question isn't very difficult: I made a part of an Android Game in Unity C# Android. When I wanted to test the game I recognised that the screen isn't automaticly in landscape mode. So I copied the AndroidManifest.xml to Assets/Plugins/Android and wrote: android:screenOrientation="landscape" When I bulit the game I saw that the Main AndroidManifest is like the Manifest on Assets/Plugins/Android but in the normal Manifest i says:android:screenOrientation="fullSensor". So when I start the game it isn't in Landscape mode. Thank you for your time!