public async Task <IActionResult> SendMail()
        {
            var filePath = _hostingEnvironment.ContentRootPath + @"/ProjectNotes/VoucherDetails.pdf";
            var result   = await _ISendGridEmailSender.Execute(filePath);

            Thread.Sleep(3000);

            ViewBag.SendGridStatusCode = result.Item1;
            ViewBag.SendGridHeaders    = result.Item2.Replace("\r\n", " <***> ");
            ViewBag.SendGridBody       = result.Item3.Replace("\r\n", " <***> ");

            return(await Task.Run(() => View()));
        }