Email view not found for 'model' in Postal.MVC - asp.net-mvc

Question

I am using Postal.MVC5 in my ASP MVC5 project. Initially i had my smtp configuration in web.config so this piece of code was working just fine and was able to send email successfully.
public async Task<ActionResult>SendEmail(EmployeeViewModel emailModel)
{
string _errorMessage;
emailModel.To = "john#outlook.com";
emailModel.Subject = "Test Subject";
emailModel.Message = "Test Message";
await emailModel.SendAsync();
return Json(new {ErrorMessage = _errorMessage});
}
Now, i need to setup Smtpclient during runtime and followed steps shown in this stackoverflow post: How to Set SMTP Client in POSTAL MVC not in WEB.Config
public async Task<ActionResult>SendEmail(EmployeeEmailViewModel emailModel)
{
string _errorMessage;
emailModel.To = "john#outlook.com";
emailModel.Subject = "Test Subject";
emailModel.Message = "Test Message";
//new code
SmtpClient client = new SmtpClient("smtp.test.com");
client.UseDefaultCredentials = false;
client.Credentials = new NetworkCredential("secretId", "notSecretPassword");
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.Port = 111;
client.EnableSsl = true;
Postal.EmailService emailService = new EmailService(new ViewEngineCollection(), () => client);
await emailService.SendAsync(emailModel);
return Json(new {ErrorMessage = _errorMessage});
}
Now this code throws an error something like this:
System.Exception: Email view not found for EmployeeEmailViewModel. Locations searched:
at Postal.EmailViewRenderer.CreateView(String viewName, ControllerContext controllerContext)
at Postal.EmailViewRenderer.Render(Email email, String viewName)
I do have 'EmployeeEmailViewModel' view in ~/Views/Emails/EmployeeEmailViewModel.cshtml .
Any idea why i am getting this error message or how i can resolve it?
Thanks
Sanjeev