I am following [Sendgrid laravel integration using smtp](https://sendgrid.com/docs/Integrate/Frameworks/laravel.html) to send email.

I did as the documentation says, all credentials are same as my sendgrid credentials.

But whenever I try to send email using,

```
Mail::send('mails.demo', $data, function($message)
        {
            $message->to('test@gmail.com', 'test')->subject('This is a test mail!');
        });

```

It shows error as 

```
Swift_TransportException in AbstractSmtpTransport.php line 383:
Expected response code 250 but got code "550", with message "550 Unauthenticated senders not allowed
"

```

I can send email using sendgrid test using [Telnet guide](https://sendgrid.com/docs/Classroom/Troubleshooting/Delivery_Issues/testing_your_connectivity_to_sendgrids_smtp_relay_using_telnet.html), that works perfectly.