Android sensors return the same values for every app opening

Every time I open my app, I get the device's orientation values. If I turn the device 90 degrees to the right at the X-axis, the values change as well. But every time I reopen my app, it shows that the X value is 348. Even if I rotated the phone 90 degrees before opening my app. Why do the sensors return the same value at the start?

Whu every time I entry the app, the starting points are always the same?

I rotated the device before opening the app to 0 degrees and got:

I rotated the device before opening the app to 90 degrees and got:

I'm rotating the correct axis, this is not the problem

My code:

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

        sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
        sensor = sensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION);

        sensorManager.registerListener(MainActivity.this, sensor, SensorManager.SENSOR_DELAY_FASTEST);
    }

    @Override
    public void onSensorChanged(SensorEvent event) { // Activated every changes in sensors
        Log.i(TAG, event.values[0] + " | " + event.values[1] + " | " + event.values[2]); // Prit the sensors values
    }

    @Override
    public void onAccuracyChanged(Sensor sensor, int accuracy) {

    }

from Android sensors return the same values for every app opening