Apparently, the issue was caused by not instantiating the assets from the main thread.

I made a custom implementation for forcing the method to run in the main thread, and it is now solved.

Apparently, the issue was caused by not instantiating the assets from the main thread.

I made a custom implementation for forcing the method to run in the main thread, and it is now solved.

This is the class that I created to force a method to run in the main thread:

using System.Collections.Generic;
using UnityEngine;

public class UnityMainThreadDispatcher : MonoBehaviour
{
public static UnityMainThreadDispatcher _instance;
private static Queue<System.Action> _actionQueue = new 
   Queue<System.Action>();

private void Awake()
{
    if (!Application.isBatchMode)
    {
        Destroy(this.gameObject);
    }

    if (_instance != null)
    {
        Destroy(gameObject);
    }
    else
    {
        _instance = this;
        DontDestroyOnLoad(gameObject);
    }
}

void Update()
{
    lock (_actionQueue)
    {
        while (_actionQueue.Count > 0)
        {
            _actionQueue.Dequeue().Invoke();
        }
    }
}

public void ExecuteOnMainThread(System.Action action)
{
    lock (_actionQueue)
    {
        _actionQueue.Enqueue(action);
    }
}
}

Then, for all the code that I want to force to the main thread, I use this:

        UnityMainThreadDispatcher._instance.ExecuteOnMainThread(async () =>
    {
       // Enter code here
    });