Firebase in Data Change is called multiple times in add event event

I have set up two listeners

• Request to get the last message
• If the last message is a group type, I get the group information using the group Listener

However, when I get the message type using messageListener and set the groupListener, it returns multiple onDataChange Debug.e("parentsnap",dataSnapshot.getValue().toString());

called more than once How do I do this please send

    groupListener = new ValueEventListener() {
        @SuppressWarnings("unchecked")
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            Debug.e("parent snap", dataSnapshot.getValue().toString());
            for (DataSnapshot d :
                    dataSnapshot.getChildren()) {
           //my code
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    };
    groups.child(chatId).addValueEventListener(groupListener);