Error: fitBounds: latLngBounds must be of type LatLngBounds.

[andrzej-wisla]

Sometimes I receive this error, what does it means?
Where I can add type to latLngBounds.

setViewport() {
    const sw = new google.maps.LatLng(this.places.viewportSwLat, this.places.viewportSwLng;
    const ne = new google.maps.LatLng(this.places.viewportNeLat, this.places.viewportNeLng;

    this.map.fitBounds(new google.maps.LatLngBounds(sw, ne));
  }