How do I use Intent for working perfekt in Android Studio

Question

I try to get a variable on my Android App from 1 Activite to an other. Ther for I using Intent but I have a Problem with it and I can´t find any answer for it. When I lauch the programm it say´s me every time 90 no matter waht I do.

MainActivitie

`public class MainActivity extends AppCompatActivity {

public static final String EXTRA_NUMBER = "com.example.akkuapp.EXTRA_NUMBER";

int level;
public TextView battery;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    battery = (TextView) this.findViewById(R.id.textakku);
    this.registerReceiver(this.mBatInfoReceiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));



    AlarmManager alarmManager = (AlarmManager) MainActivity.this.getSystemService(ALARM_SERVICE);
    Intent startServiceIntent = new Intent(MainActivity.this, Hintergrundservice.class);

    PendingIntent startServicePendingIntent = PendingIntent.getService(MainActivity.this, 0, startServiceIntent, 0);

    Calendar calendar = Calendar.getInstance();


    calendar.setTimeInMillis(System.currentTimeMillis());
    long time = calendar.getTimeInMillis();



    alarmManager.setInexactRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), 1000 * 5, startServicePendingIntent);

}


public final BroadcastReceiver mBatInfoReceiver = new BroadcastReceiver() {
    @SuppressLint("SetTextI18n")
    @Override
    public void onReceive(Context context, Intent intent) {
        level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, 0);
        battery.setText(String.valueOf(level) + '%');

        intent.putExtra(EXTRA_NUMBER, level);
    }
};

Backgroundservice

` @Override public int onStartCommand(Intent intent, int flags, int startId) {

        level = intent.getIntExtra(MainActivity.EXTRA_NUMBER,90);
        Toast.makeText(getApplicationContext(), String.valueOf(level), Toast.LENGTH_LONG).show();
        Log.d("Hintergrundprozess", String.valueOf(level));



    return flags;
}



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

Pictur MainActivity

Pictur Hintergrundprozess (Backgroundservice)

Thank you for your Help