Problem with Firestore Snapshot Listener in Android Compose and Callback Lambda - kotlin

Question

In my Compose Project I wanted to implement a Snapshot Listener that updates the LiveData of my ViewModel. To keep the code related to firestore apart from logic in the viewModel I added a Repository with the following funtion:
override fun getInvitations(onDataUpdate: (List<Session>) -> Unit) {
val invitationsQuery = db.collection("invitations").whereEqualTo("player_id", auth.currentUser?.uid)
val listener = invitationsQuery.addSnapshotListener{ querySnapshot, exception ->
if (exception != null){
Log.w("ONLINE", "Error handling Snapshot",exception)
return#addSnapshotListener
}
val sessions = mutableListOf<Session>()
querySnapshot?.documents?.forEach{
sessions.add(it.toSession())
}
onDataUpdate(sessions)
}
listeners.add(listener)
}
The idea was then to only call this function once in the viewModel and give it a Lambda that updates the LiveData like this:
multiplayerRepository.getInvitations {
invitations.value = it
}
The problem is that there is no Recomposition caused although the LiveData gets updated. Multiple Logs gave me that.
I already tried using postValue() instead of invitations.value = ...with no other effect.
I really want to keep the LiveData away from the Repository, but am aware it will be an alternative to get the LiveData from the Listener.
Anything appreciated.

Answer 1

The solution to my problem was rather simple.
This was not a problem of Compose nor was Firebase doing weird stuff. It was the Code I wrote.
It turned out that I overlooked that I deleted a function that queries Userdata when I deleted another old function. Without it my UI cannot update due to a empty list.
I went through my commits multiple times and missed it multiple times. But the moment I saw that was a great relief.
Still thanks to all your help.