Firebase observer setting values initially, but not updating when changes are made - ios

Question

I tried to set up a function to listen for changes within a certain part of my database:
private func observeParticipants() {
let databaseRef = FIRDatabase.database().reference()
let groupRef = databaseRef.child("groups").child(currentRoomID).child("participants")
groupRef.observe(.childAdded, with: { snapshot in
print("observe snapshot.value: \(snapshot.value)")
if let snapDict = snapshot.value as? [String:AnyObject] {
for each in snapDict {
let uid = each.key
let avatar = each.value["profilePicture"] as! String
let gender = each.value["gender"] as! String
let handle = each.value["handle"] as! String
let name = each.value["name"] as! String
let status = each.value["status"] as! String
// Set those to the dictionaries [UID : value]
self.avatarDictionary.setValue(avatar, forKey: uid)
self.nameDictionary.setValue(name, forKey: uid)
self.genderDictionary.setValue(gender, forKey: uid)
self.handleDictionary.setValue(handle, forKey: uid)
self.statusDictionary.setValue(status, forKey: uid)
print("\n\navatarDictionary:\n \(self.avatarDictionary)")
print("\nhandleDictionary:\n \(self.handleDictionary)")
print("\ngenderDictionary:\n \(self.genderDictionary)")
print("\nnameDictionary:\n \(self.nameDictionary)")
print("\nstatusDictionary:\n \(self.statusDictionary)")
self.navBarCollectionView.reloadData()
}
}
})
}
When I run this, it loads the correct values, but if I make a change, for example add a new user to the group, it doesn't reflect that change. The database is updated fine, but the observer isn't seeing that. Is there any way I can re-write this to make is observe properly? I can post my database structure if it will help.
Thanks!
EDIT: Database structure:
https://pastebin.com/SZ2mE2Vt
EDIT: snapshot.value after adding second user:
Snapshot.value: Optional({
gender = female;
handle = sav;
name = Savina;
profilePicture = "https://graph.facebook.com/1929991317219760/picture?type=large&return_ssl_resources=1";
status = F8B016;
})
EDIT 2:
This is the code that works for fetching all user values initially, and also every time I leave the view and come back. It just doesn't act properly as an observer, i.e. if I add a participant, it doesn't see that and update the necessary values such as the collection view. I have to leave the view and come back for that to happen.
func getParticipantInfo() {
let databaseRef = FIRDatabase.database().reference()
let groupRef = databaseRef.child("groups").child(currentRoomIdGlobal)
groupRef.observe(.childAdded, with: { snapshot in
if let snapDict = snapshot.value as? [String : AnyObject] {
for each in snapDict {
let uid = each.key
let avatar = each.value["profilePicture"] as! String
let gender = each.value["gender"] as! String
let handle = each.value["handle"] as! String
let name = each.value["name"] as! String
let status = each.value["status"] as! String
// Set those to the dictionaries [UID : value]
self.avatarDictionary.setValue(avatar, forKey: uid)
self.nameDictionary.setValue(name, forKey: uid)
self.genderDictionary.setValue(gender, forKey: uid)
self.handleDictionary.setValue(handle, forKey: uid)
self.statusDictionary.setValue(status, forKey: uid)
print("\n\navatarDictionary:\n \(self.avatarDictionary)")
print("\nhandleDictionary:\n \(self.handleDictionary)")
print("\ngenderDictionary:\n \(self.genderDictionary)")
print("\nnameDictionary:\n \(self.nameDictionary)")
print("\nstatusDictionary:\n \(self.statusDictionary)")
self.navBarCollectionView.reloadData()
}
}
})
}