Export database record from View to PDF using Rotativa in ASP.Net MVC

Hello, I wrote a pdf code in asp.net mvc, but it works when there is no database, it does not work when there is a database. I am sending the codes.

I would be very happy if you find a solution.

using Rotativa;
public ActionResult Index()
{
      var ad = (string)Session["FIRMAKODU"];
      var plasiyerid = (string)Session["PLASIYERID"];
      var kullaniciid = (string)Session["KULLANICIADI"];
      ViewBag.ad = ad;
      ViewBag.plasiyerid = plasiyerid;
      var anamenu = db.WEBAYARLAR.Where(x => x.FIRMAKODU == ad & x.PLASIYERID == plasiyerid & x.KULLANICIADI == kullaniciid).ToList();
      if (ad != null)
      {
          return View(anamenu);

      }
      else
      {
          return RedirectToAction("Login", "Menu");
      }
}

[HttpPost]
public ActionResult GeneratePdf()
{
      var htmlContent = "Merhaba Samet"; // PDF'ye dönüştürmek istediğiniz metin

      var pdfBytes = GeneratePdfBytes(htmlContent);

      return File(pdfBytes, "application/pdf", "Belge.pdf");
}

private byte[] GeneratePdfBytes(string htmlContent)
{
      var pdf = new ViewAsPdf
      {
          ViewName = "Index",
          IsGrayScale = false,
          FileName = "Belge.pdf",
          PageSize = Rotativa.Options.Size.A4,
          PageMargins = new Rotativa.Options.Margins(10, 10, 10, 10)
      };

      return pdf.BuildFile(ControllerContext);
}

@using samkasaha.Models.Siniflar
@model List<WEBAYARLAR>
@{
    ViewBag.Title = "Index";
    Layout = "~/Views/Shared/View.cshtml";
}
<script src="https://code.jquery.com/jquery-3.6.4.min.js"></script>
@foreach (var a in Model)
{
    <h1>@a.FIRMAADI</h1>
    <h1>@a.KULLANICIADI</h1>
    <h1>@a.GUNCELLEME</h1>
    <img src="@a.LOGO" />
}
<div id="pdfDiv" style="display: none;">

    @using (Html.BeginForm("GeneratePdf", "Menu", FormMethod.Post))
    {
        <input type="submit" value="PDF Oluştur" />
    }
</div>

<div id="htmlDivContent">
    @foreach (var a in Model)
    {
        <h1>@a.FIRMAADI</h1>
        <h1>@a.KULLANICIADI</h1>
        <h1>@a.GUNCELLEME</h1>
        <img src="@a.LOGO" />
    }
</div>

<script>
    $(document).ready(function () {
        // PDF div'inin görünürlüğünü kontrol et
        function checkPdfVisibility() {
            var pdfDivVisible = $("#pdfDiv").is(":visible");
            $("#htmlDivContent").toggle(!pdfDivVisible);
        }

        // Sayfa yüklendiğinde PDF div'i gizli
        checkPdfVisibility();

        // PDF div'inin görünürlüğünü kontrol et ve içeriği gizle
        $("#pdfDiv").show(function () {
            checkPdfVisibility();
        });
    });
</script>