private void OnDestroy()
 {
     if (uiCanvas != null)
     {
         instance = null;
     }
 }
        private void Awake()
        {
            if (instance != null && instance != this)
            {
                Destroy(gameObject);
                return;
            }

            instance = this;

            if (uiCanvas != null)
            {
                DontDestroyOnLoad(gameObject);
            }
        }