public ActionResult Index(string username = null, string password = null)
    {
        if (username == null || password == null)
        {
            return RedirectToAction("Index", "Auth");
        }

        this.username = username;
        this.password = password;

        ViewBag.Message = "Call Recordings Web Application!";
        return View(); //and have tried return View("Index");
    }

[HttpGet]
    public ActionResult Login(string username, string password)
    {
        return Redirect("~/Home/Index?username="+username+"&password="+password);
    }