getting duplicate data while fetch messages list firebase - ios

Question

Hello i am creating Chat App Using Swift And Firebase i am fetching messages and populating in tableview but when i send new message then tableview dislplaying multiple entry i am useing below code for fetching messages
func fetchAllMessage(){
guard let uid = Auth.auth().currentUser?.uid else { return }
let fetchMsgGroup = Database.database().reference().child("user-messages_group_iOS").child(uid).child(self.chatID)
fetchMsgGroup.observe(.value, with: { (snapshot) in
if snapshot.exists(){
if let dictonary = snapshot.value as? [String:AnyObject]{
self.groupMessageData.removeAll()
if let userMessages = dictonary["userMessages"] as? [String:AnyObject]{
for (key, _) in userMessages{
let messagesFrtchRef = Database.database().reference().child("messages_iOS").child(key)
messagesFrtchRef.observe(.value, with: { (snapshot1) in
if snapshot1.exists(){
if let dict = snapshot1.value as? [String:AnyObject]{
let fromId = dict["fromId"] as! String
let messageUID = dict["messageUID"] as! String
let seen = dict["seen"] as! Bool
let status = dict["status"] as! String
let text = dict["text"] as! String
let timestamp = dict["timestamp"] as! Double
let told = dict["told"] as! String
let messages = GroupMessage(fromId: fromId, messageUID: messageUID, seen: seen, status: status, text: text, timestamp: timestamp, told: told)
self.groupMessageData.insert(messages, at: 0)
}
self.tblListView.reloadData()
}else{
}
}, withCancel: nil)
}
}
}
}else{
}
}, withCancel: nil)
}
i have tried everything like clearing removing also clearing observer when needed but its not work enough for me is their anyone have any solution for this then please help me
can anyone help me to solve this out