onLocationChanged not being called android java : Three months ago my code works fine, but now it didn't work. Exactly onLocationChenged not being called and I don't know why. I haven't chnged anything for this 3 months. Also when I want to show marker on the map, it doesn't exist. I have every permission which I need. Below there is a code in java (android):

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

            new DecimalFormat("#.#", new DecimalFormatSymbols(Locale.US));
    
    		OnClickListener();
    
    		mapFragment = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map));
    		if (mapFragment != null) {
    			mapFragment.getMapAsync(new OnMapReadyCallback() {
    				@Override
    				public void onMapReady(GoogleMap map) {
    					loadMap(map);
    				}
    			});
    		} else {
    			Toast.makeText(this, "Error - Map Fragment was null!!", Toast.LENGTH_SHORT).show();
    		}

            Marker("50.06465", "19.94498", "Example");
    
    	}

.

        public void onLocationChanged(Location location) {

		mLAT = Double.toString(location.getLatitude());
		mLON = Double.toString(location.getLongitude());

		new DoIt().execute();

	}

        public void Marker(String LAT, String LON, String tit) {

		double dLAT = Double.parseDouble(LAT);
		double dLON = Double.parseDouble(LON);

		LatLng pos = new LatLng(dLAT, dLON);

		if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
			// TODO: Consider calling
			return;
		}

		map.setMyLocationEnabled(true);

		singleMarker = map.addMarker(new MarkerOptions()
				.title(tit)
				.position(pos)
				.icon(BitmapDescriptorFactory.fromResource(R.mipmap.icon));

	}