Не работает NotificationManagerCompat

Столкнулся с проблемой, долго пытался найти решение, но так и не нашел. Суть в том, что при запуске фонового сервиса должно появится уведомление где есть возможность переключать треки, ставить на паузу и т.п. Но пишет ошибку.

I/ERROR notify:: Attempt to invoke virtual method 'void androidx.core.app.NotificationManagerCompat.notify(java.lang.String, int, android.app.Notification)' on a null object reference

BackgroundSoundService.java ``

public class BackgroundSoundService extends Service {

public static final String CHANNEL_ID = "channel1";
public static NotificationManagerCompat notificationManagerCompat;

MediaPlayer mediaPlayer;
String urls, names, author;


@Nullable
@Override
public IBinder onBind(Intent intent) {
    return null;
}

@Override
public void onCreate() {
    super.onCreate();

}


@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN)
public int onStartCommand(Intent intent, int flags, int startId) {
    names = intent.getStringExtra("names");
    author = intent.getStringExtra("author");
    urls = intent.getStringExtra("urls");

    mediaPlayer = MediaPlayer.create(this, Uri.parse(urls));
    mediaPlayer.setLooping(true); // Set looping
    mediaPlayer.setVolume(100, 100);
    //mediaPlayer.start();

    musicNotification();

    Toast.makeText(getApplicationContext(), "Playing Bohemian Rashpody in the Background",    Toast.LENGTH_SHORT).show();
    return startId;
}

public void onStart(Intent intent, int startId) {

}

@Override
public void onDestroy() {
    mediaPlayer.stop();
    mediaPlayer.release();
}

@Override
public void onLowMemory() {

}

@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN)
public void musicNotification(){
    Bitmap atwork  = BitmapFactory.decodeResource(getResources(), R.drawable.ic_music_36);

    Notification notification = new NotificationCompat.Builder(BackgroundSoundService.this, CHANNEL_ID)
            .setSmallIcon(R.drawable.ic_pause_24)
            .setContentTitle("ddd")
            .setContentText("ddee")
            .setLargeIcon(atwork)
            .addAction(R.drawable.ic_previous_24, "previous", null)
            .addAction(R.drawable.ic_pause_24, "pause", null)
            .addAction(R.drawable.ic_next_24, "next", null)
            .setPriority(NotificationCompat.PRIORITY_DEFAULT)
            .build();
    try{
        notificationManagerCompat.notify(null, 1, notification);
    } catch (Exception e){
        Log.i("ERROR notify:", e.getMessage());
    }
}

}

AndroidManifest.xml

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:usesCleartextTraffic="true"
    android:theme="@style/AppTheme">
    <activity android:name=".PlayerActivity">

    </activity>
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <service android:name=".BackgroundSoundService" />
</application>