Event listener not working with firebase query

I am trying to create an event listener to my firebase query script but it acts a little strange?!?

Here is my script:

using System.Collections.Generic;
using UnityEngine;
using System.Linq;
using UnityEngine.Events;
using Firebase.Firestore;
 
public class TestDataHandler : MonoBehaviour
{
 
    public GameObject testObject;
 
    private void Start()
    {
        fbEvent.AddListener(readyToGo);
        GetUserData("12345");
    }
 
    void readyToGo()
    {
        Debug.Log("Do Stuff");
        tetsObject.SetActive(false);
        Debug.Log("Stuff Done");
    }
 
    UnityEvent fbEvent = new UnityEvent();
 
    public void GetUserData(string userId)
    {
 
        Query query = FirebaseDataManager.instance.users
            .WhereEqualTo("userId", userId
            );
 
        query.GetSnapshotAsync().ContinueWith(querySnapshotTask =>
        {
           
            if (querySnapshotTask.IsFaulted)
            {
                Debug.Log("No userdata is found");
            }
            else if (querySnapshotTask.Result.Documents.Count() < 1)
            {
                Debug.Log("No userdata is found");
            }
            else
            {
                DocumentSnapshot userData = querySnapshotTask.Result.Documents.FirstOrDefault();
                Dictionary<string, object> data = userData.ToDictionary();
 
                User tempUser = FirebaseSerializer.FBDataToObject(data) as User;
 
                Debug.Log("Userdata found: " + tempUser.firstName);
 
                fbEvent.Invoke();
            }
        });
    }
 
}

It kinda works, course the listener listens but I am not able to, in this example, deactivate an gameobject from the listener return function.

I get the "Do Stuff" log, but not the "Stuff Done" log and the GameObject is not deactivated?

What am I missing here?