Importing XLSX file in Blazor Web Assembly for .NET 5.0 is very slow.

          <InputFile OnChange="@HandleFileSelected" />

async Task HandleFileSelected(InputFileChangeEventArgs e)

{

   var ms = new MemoryStream((int)e.File.Size);
        Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.XlsxFormatProvider formatProvider = new Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.XlsxFormatProvider();
        using (Stream ey = e.File.OpenReadStream(e.File.Size))
        {
            await ey.CopyToAsync(ms,(int)e.File.Size);
            ey.Close();
        }
        oWorkbook = formatProvider.Import(ms);

  }