iOS firebase observer delays observing the changes in the node - ios

Question

I have one function to get the realtime location updates of the selected user.
And in that function , i need to call the current status and history of that selected user from the firebase.
So, the problem is when I start my observer for location updates only , it's fine and it's great .
I get the value from firebase observer.
But , when i make a call for current status and history of that selected user , I am getting the delay in my firebase realtime observer .
I don't understand how come call to another firebase is affecting our realtime observer code.
Guys any suggestions,
I tried dispatching to background for current status /history call but still no luck.
Left me hopeless and clueless.
Added:
I am getting current status and realtime observers from the same node.
So , does this happens that same node is observing and same time if another firebase call is made to same node , is it colliding ???
UPDATED
Firebase function to get current status :
FIRDatabaseReference().child("personal").child(userUUID).child("realtime")
.observeSingleEvent(of: .value, with: { (snapshot) in
//print(snapshot.key)
if snapshot.exists(){
let location = LocationParser(dict: snapshot.value as! [String : AnyObject])?.location
completion(location)
}else{
completion(nil)
}
}){ (error) in
completion(nil)
debugPrint(error.localizedDescription)
}
Firebase function to observe location (continuously):
FIRDatabaseReference().child("personal").child(userUUID).child("realtime")
.observe(.value) { (snapshot:FIRDataSnapshot) in
print("\nOBSERVER FROM FIREBASE FIRED")
if let value = snapshot.value as? [String:AnyObject] {
if let location = LocationParser(dict: value)?.location {
//we cannot save location to our database
//sharedFirebaseManager.saveLocationHistoric(LocationParser(dict: value)!)
result(success(location))
}
}
}
QUESTION:
I am calling both from the same controller and I see continuous observer delays on calling another firebase function call.
Any clue.