Fused Location Provider method getLastLocation() returning null values

Question

I am implementing a location android app , using fused location provider client .It has been working few days ago but actually it craches because it is returning as value null and here is what i got as error message : java.lang.NullPointerException: Attempt to invoke virtual method 'double android.location.Location.getLongitude()' on a null object reference . How could i figure it out? Here is the code i have implemented :

fusedLocationProviderClient.getLastLocation()
            .addOnSuccessListener(baseView, position -> {
                Log.d("TAG", "updateGPS: position elements are : " + "lon = " + position.getLongitude() + "lat = " + position.getLatitude() + "alt " + position.getAltitude() + "Acc= " + position.getAccuracy() + " Speed = " + position.getSpeed());
                if (position.getAccuracy() <= 20f) {
                    location.setLongitude(position.getLongitude());
                    location.setLatitude(position.getLatitude());
                    location.setAltitude(position.getAltitude());
                    location.setAccuracy(position.getAccuracy());
                    location.setSpeed(position.getSpeed());
                }

here is my callback method :

locationCallback = new LocationCallback() {
        @Override
        public void onLocationResult(@NonNull LocationResult locationResult) {
            super.onLocationResult(locationResult);

            Location location = locationResult.getLastLocation();
            assert location != null;
            Log.d("TAG", "onLocationResult: callback method  " + "longitude " + location.getLongitude() + "latitude " + location.getLatitude() + "Accuracy " + location.getAccuracy() + "Speed " + location.getSpeed());
        }
};

and here is the update settings :

public void locationSettings() {
    //Put in the time service
    newlocationRequest = new LocationRequest();
    newlocationRequest.setInterval(30000);
    newlocationRequest.setFastestInterval(5000);
    //most accurate use GPS
    newlocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
    startLocationUpdate();
}

and finally here is the update function :

public void startLocationUpdate() {

    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && 
        ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                // TODO: Consider calling
                //    ActivityCompat#requestPermissions
                // here to request the missing permissions, and then overriding
                //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                //                                          int[] grantResults)
                // to handle the case where the user grants the permission. See the documentation
                // for ActivityCompat#requestPermissions for more details.
        return;
    }

    fusedLocationProviderClient.requestLocationUpdates(newlocationRequest, locationCallback, Looper.myLooper());
    //  updateGPS();
    
}