title: Laravel Notifications: Mail (Mailgun) Response on NotificationSent event
body: <p>I am using Mailgun as a mail driver in my laravel application, as well as nexmo for SMS purposes.</p>
  
  <p>What I am trying to achieve is to maintain the delivery status of the notifications that are sent either via Mailgun or Nexmo. Incase of Nexmo I am able achieve this, since I get the nexmo MessageId in the NotificationSent event that is fired after processing a notification.</p>
  
  <p>However in the event instance for email, the response is empty.</p>
  
  <p>Any idea what I am missing or, how I can retrieve the mailgun message-id?</p>