Display Only Mapkit Annotations From Firebase Created Within The Last Hour - swift

Question

I am currently able to pull down all of my annotations from Firebase Firestore and display them with no problem. In my snapshot listener I would like to be able to only display annotations created within the last hour. I've included my code below that isn't working and is still returning all annotations in my Firestore.
let hourAgo = Date().addingTimeInterval(-3600)
db.collection("pins").addSnapshotListener { QuerySnapshot, Error in
guard let documents = QuerySnapshot?.documents else {
print("No documents")
return
}
let annotation = documents.map { QueryDocumentSnapshot -> Pin in
let data = QueryDocumentSnapshot.data()
let latitude = data["latitude"] as? Double ?? 0.0
let longitude = data["longitude"] as? Double ?? 0.0
let eventTitle = data["eventTitle"] as? String ?? ""
let eventSubtitle = data["eventSubtitle"] as? String ?? ""
let lastUpdated = data["lastUpdated"] as? Timestamp ?? Timestamp.init()
let pinDate = lastUpdated.dateValue()
let coordinate = CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
if pinDate >= self.hourAgo {
self.displayPins(coordinate: coordinate, eventSubtitle: eventSubtitle, eventTitle: eventTitle)
}else{
return Pin(latitude: latitude, longitude: longitude, eventTitle: eventTitle, eventSubtitle: eventSubtitle)
}
//print(annotation)
return Pin(latitude: latitude, longitude: longitude, eventTitle: eventTitle, eventSubtitle: eventSubtitle)
}
}
}
func displayPins(coordinate: CLLocationCoordinate2D, eventSubtitle: String, eventTitle: String) {
let annotation = MKPointAnnotation()
annotation.coordinate = coordinate
annotation.title = eventTitle
annotation.subtitle = eventSubtitle
mapView.addAnnotation(annotation)
}```