private void Awake()
 {
     if (instance == null)
     {
         instance = this;
     }
     else if (instance != this)
     {
         Destroy(this.gameObject);
     }
 }
 private void Awake()
 {
     if (instance == null)
     {
         instance = this;
     }
     else if (instance != this)
     {
         Debug.Log("Wave Instance already exist, destroy this Obj!");
         Destroy(this);
     }
 }