YouTube player implementation

     package com.example.stm;        import androidx.appcompat.app.AppCompatActivity;        import android.os.Bundle;        import android.widget.Toast;        import com.google.android.youtube.player.YouTubeInitializationResult;        import com.google.android.youtube.player.YouTubePlayer;        import com.google.android.youtube.player.YouTubePlayerView;        public class Youtube extends AppCompatActivity {            YouTubePlayerView youTubePlayerView;            String adres = "https://www.youtube.com/watch?v=u8QppD8yqdc";            String toster = "Initialization failed";            String apikey = "AIzaSyDYaN0HY-2GG6BKJ4oMp0_fDmTJ2o";            @Override            protected void onCreate(Bundle savedInstanceState) {                super.onCreate(savedInstanceState);                setContentView(R.layout.activity_youtube);                youTubePlayerView = (YouTubePlayerView) findViewById(R.id.player);                YouTubePlayer.OnInitializedListener listener = new YouTubePlayer.OnInitializedListener() {                    @Override                    public void onInitializationSuccess(YouTubePlayer.Provider provider, YouTubePlayer youTubePlayer, boolean b) {                        youTubePlayer.loadVideo(adres);                        youTubePlayer.play();                    }                    @Override                    public void onInitializationFailure(YouTubePlayer.Provider provider, YouTubeInitializationResult youTubeInitializationResult) {                        Toast.makeText(getApplicationContext(),toster, Toast.LENGTH_SHORT).show();                    }                };                youTubePlayerView.initialize(apikey, listener);            }        }<com.google.android.youtube.player.YouTubePlayerView        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/player"        android:layout_centerInParent="true"/>

Hello guys! I`m trying to build in youtube player in my app. This is my code. When i press button to start activity, it starts, but then stops and returns back to parent activity. Please help to find out what is wrong. Thank you.