Taking latitude & longitude from Cloud Firestore and adding them to Mapbox as annotation - ios

Question

I'm trying to retrieve the flight number, latitude & longitude from all Firestore documents and add them as Mapbox annotations to a mapView. So far the code pulls the data from Cloud Firestore and stores them as variables. Aditionally the code displays a Mapbox map with coordinates but they must be assigned manually in the array
Im having trouble with appending the variables from Firestore to the coordinates array.
I found this "Add annotation after retrieving users latitude and longitude from Firebase" which was along the correct lines but its to do with firebase and not firestore.
Any help would be greatly appreciated!
class HomeViewController: UIViewController, MGLMapViewDelegate {
override func viewDidLoad() {
super.viewDidLoad()
let mapView = MGLMapView(frame: view.bounds)
mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
mapView.styleURL = MGLStyle.darkStyleURL
mapView.tintColor = .lightGray
mapView.centerCoordinate = CLLocationCoordinate2D(latitude: 0, longitude: 66)
mapView.zoomLevel = 2
mapView.delegate = self
view.addSubview(mapView)
var aircraftArray = [""]
let db = Firestore.firestore()
let AircraftRef = db.collection("LiveAircraftData").getDocuments { (snapshot, err) in
if let err = err {
print("Error getting documents: \(err)")
} else {
for document in snapshot!.documents {
let FlightNumber = document.documentID
let latitude = document.get("Latitude") as! Double
let longitude = document.get("Longitude") as! Double
print(FlightNumber, latitude, longitude)
var Coordinates = CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
aircraftArray.append(Coordinates)
var pointAnnotations = [MGLPointAnnotation]()
for coordinate in Coordinates {
let point = MGLPointAnnotation()
point.coordinate = coordinate
point.title = "\(coordinate.latitude), \(coordinate.longitude)"
pointAnnotations.append(point)
}
mapView.addAnnotations(pointAnnotations)
}
}
}
}
This is what my database looks like
screenshot of code