Firebase database now only displaying newly added annotations on map - ios

Question

I have an app that allows people to put annotations on a map that get stored in a Firebase database, I have recently been trying to add a new feature to the app so to avoid messing about with my real database I created another app in firebase and used it for me to do my testing on. I deleted the GoogleService-Info.Plist and imported the one for the new test app but now when I delete the test GoogleService-Info.Plist and replace it with the one that works with my Live app none of my annotations show up on the map, but any I create from that point onwards will show up.
I've done a clean and build but still the same result. All the data is still there in my original database as my AppStore version of the app works exactly as it should, I really don't know what could be wrong here, I'll let you see what my code is for retrieving the annotations, in case that helps you with your answer.
import UIKit
import MapKit
import Firebase
class MapViewController: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate {
#IBOutlet weak var mapView: MKMapView!
#IBOutlet weak var postboxesLoggedLabel: UILabel!
var locationManager = CLLocationManager()
let annotation = MKPointAnnotation()
override func viewDidLoad() {
super.viewDidLoad()
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.requestWhenInUseAuthorization()
locationManager.startUpdatingLocation()
displayAnnotations()
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let userLocation: CLLocation = locations[0]
let latitude = userLocation.coordinate.latitude
let longitude = userLocation.coordinate.longitude
let latDelta: CLLocationDegrees = 0.05
let lonDelta: CLLocationDegrees = 0.05
let span = MKCoordinateSpan(latitudeDelta: latDelta, longitudeDelta: lonDelta)
let location = CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
let region = MKCoordinateRegion(center: location, span: span)
self.mapView.setRegion(region, animated: true)
locationManager.stopUpdatingLocation()
}
func displayAnnotations() {
let ref = Database.database().reference()
ref.child("Postbox").observe(.childAdded, with: { (snapshot) in
let monToFri = (snapshot.value as AnyObject!)!["Monday to Friday Collection Time"] as! String!
let sat = (snapshot.value as AnyObject!)!["Saturday Collection Time"] as! String!
let latitude = (snapshot.value as AnyObject!)!["Latitude"] as! String!
let longitude = (snapshot.value as AnyObject!)!["Longitude"] as! String!
let lastCollection = "Mon - Fri: \(monToFri!)" + " Sat: \(sat!)"
self.annotation.coordinate = CLLocationCoordinate2D(latitude: (Double(latitude!))!, longitude: (Double(longitude!))!)
self.annotation.title = "Last Collection:"
self.annotation.subtitle = lastCollection
self.mapView.addAnnotation(self.annotation)
self.postboxesLoggedLabel.text = String(self.mapView.annotations.count)
})
}
/* func removeAnnotation(gesture: UIGestureRecognizer) {
if gesture.state == UIGestureRecognizerState.ended {
self.mapView.removeAnnotation(annotation)
print("Annotation Removed")
}
} */
#IBAction func myLocation(_ sender: Any) {
locationManager.startUpdatingLocation()
}
#IBAction func mapType(_ sender: Any) {
switch ((sender as AnyObject).selectedSegmentIndex) {
case 0:
mapView.mapType = .standard
case 1:
mapView.mapType = .satellite
default: // or case 2
mapView.mapType = .hybrid
}
}
}