title: In Swift, Failed to send SMS but MFMessageComposeViewController Delegate Show sent
body: <p>I am using <code>MFMessageComposeViewController</code> to send SMS from my app. </p>
  
  <p>The <code>didFinishWithResult</code> delegate method of <code>MFMessageComposeViewController</code> shows that the message has been sent successfully but actually this SMS failed to send due to insufficient balance. So <code>MFMessageComposeViewController</code> does not show me the correct result.</p>
  
  <p>How do I know that the Messages app failed to send an SMS? Is there any way to get the failed status?</p>