Getting SendGrid Server Results in ASP.Net Core - asp.net-core

Question

Here's my code to send email via SendGrid.
public Task<Result> Execute(string apiKey, string subject, string message, string email)
{
var client = new SendGridClient(apiKey);
string senderEmail = this.Configuration["Email:Address"];
string senderName = this.Configuration["Email:Name"];
var msg = new SendGridMessage()
{
From = new EmailAddress(senderEmail, senderName),
Subject = subject,
PlainTextContent = message,
HtmlContent = message
};
msg.AddTo(new EmailAddress(email));
var response = client.SendEmailAsync(msg);
return response;
}
It is able to send email confirmation and password reset emails, when invoked by ASP.Net Core Identity code.
However, when I try to send email using my own controller action (for a Contact Us feature), nothing happens.
This is the controller action.
public async Task<JsonResult> SendContactEmail(int id, string message)
{
Page page = await this.Get(id);
var result = _emailSender.SendEmailAsync(page.Email, page.Subject, message);
return new JsonResult(result);
}
Is there a way to troubleshoot this? I don't get any exceptions and the response object doesn't seem to have any useful property like a message from the SendGrid server.
UPDATE:
SendGrid's API does return an informative result. I have updated my code to return this.
https://github.com/sendgrid/sendgrid-csharp/blob/master/src/SendGrid/Response.cs