How to start game over activity? (android studio)

Question

Goal display Game over screen when health = 0;

Steps

1. create new activity (GameOver.class)
2. create layout for GameOver activity
3. create new activity in AndroidManifest.xml

       <activity
           android:name=".GameOver"
           android:exported="false" />

4. when player dies new activity is called

            if(player.heart == 0){
                Intent gameOverIntent = new Intent(context, MainActivity.class);
                context.startActivity(gameOverIntent);
            }

Error However I get this error...

   Process: com.example.breakoutgame, PID: 21386
   java.lang.NullPointerException: Attempt to invoke virtual method 'void android.graphics.Canvas.drawColor(int, android.graphics.PorterDuff$Mode)' on a null object reference
       at android.view.SurfaceView.clearSurfaceViewPort(SurfaceView.java:665)
       at android.view.SurfaceView.dispatchDraw(SurfaceView.java:610)
       at android.view.View.draw(View.java:22353)
       at android.view.SurfaceView.draw(SurfaceView.java:601)
       at com.example.breakoutgame.Game.draw(Game.java:84)
       at com.example.breakoutgame.GameLoop.run(GameLoop.java:57)

Maybe I missed some step?