SceneManager.LoadScene not working with button

Hi everyone, I'm having problem with changing current scene via a button or with a dropdown. I'm using same method with triggers at level endswhere it works but when using this with buttons new scene is loading but freeze in first frame and do not log any error message. By the way scenes are added to build index. Here is my simplified script, I use LoadGame() method with a button ;

 using UnityEngine;
 using UnityEngine.UI;
 using TMPro;
 using UnityEngine.SceneManagement;
 
 public class LoadGame : MonoBehaviour
 {
     public void LoadSelectedLevel()
     {
         SceneManager.LoadScene(2, LoadSceneMode.Single);
     }
 }