VerifyTotp always fails

[zyz]

1.VS 2022：New ASP.NET Core Web (Model-Model-Controller)
2.Install-Package Otp.NET, Install-Package QRCoder
3.HomeController.cs
using Microsoft.AspNetCore.Mvc;
using System.Diagnostics;
using Web.Models;
using OtpNet;
using QRCoder;
using System.Text;

public class HomeController : Controller
{
private readonly ILogger _logger;
private const string Secret = "JBSWY3DPEHPK3PXP";
private const string BaseUser = "test";
private const string Issuer = "demo";

public HomeController(ILogger<HomeController> logger)
{
    _logger = logger;
}

public IActionResult Index()
{
    return View();
}

public IActionResult Qrcode()
{
    string uriString = new OtpUri(OtpType.Totp, Secret, BaseUser, Issuer).ToString();

    using QRCodeGenerator qrGenerator = new();
    using QRCodeData qrCodeData = qrGenerator.CreateQrCode(uriString, QRCodeGenerator.ECCLevel.Q);
    using PngByteQRCode qrCode = new(qrCodeData);
    {
        byte[] qrCodeImage = qrCode.GetGraphic(20);
        return File(qrCodeImage, "image/jpeg");
    }
}

public IActionResult Validate(string code)
{
    var totp = new Totp(Encoding.UTF8.GetBytes(Secret));
    var verificationWindow = VerificationWindow.RfcSpecifiedNetworkDelay;
    var isValid = totp.VerifyTotp(code, out long timeWindowUsed, verificationWindow);
    return Content(isValid ? "Success" : "Fail");
}

}
4.Views/Home/Index.cshtml
@{
ViewData["Title"] = "Home Page";
}
<div class="text-center">
<h1 class="display-4">Welcome</h1>
<img src="/Home/Qrcode" style="width: 300px;" />
<form action="/Home/Validate" method="post">
Code: <input name="code" />
<input type="submit" value="Validate" />
</form>
</div>
5.run
6.Scan the QR code using APP Authenticator
7.Enter totp code, VerifyTotp always fails

[zyz]

Use Base32Encoding.ToBytes to resolve
var totp = new Totp(Base32Encoding.ToBytes(Secret));