Use of unresolved identifier 'MFMailComposeCancelled'

Im getting the error "Use of unresolved identifier 'MFMailComposeCancelled'" after setting up a contact forum like below. Has something changed/depreciated that Xcode isnt catching or am I just tired this morning?

import Foundation
import MessageUI

class Contact : UIViewController, MFMailComposeViewControllerDelegate {
    @IBOutlet weak var WOLMenu: UIBarButtonItem!
    @IBOutlet var NameField: UITextField!
    @IBOutlet var EmailField: UITextField!
    @IBOutlet var PhoneField: UITextField!
    @IBOutlet var MessageField: UITextField!




    override func viewDidLoad() {
     
        self.view.addGestureRecognizer(self.revealViewController().panGestureRecognizer())
     
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }
    @IBAction func Send(sender: AnyObject) {
        let toRecipients = ["S Jobs @ apple. com"]
     
        let mc: MFMailComposeViewController = MFMailComposeViewController()
     
        mc.mailComposeDelegate = self
     
        mc.setToRecipients(toRecipients)
        mc.setSubject(NameField.text!)
     
        mc.setMessageBody("Name: \(NameField.text!) \n\nEmail: \(EmailField.text!) \n\nPhone: \(PhoneField.text!) \n\nMessage: \(MessageField.text!)", isHTML: false)
     
        self.present(mc, animated: true, completion: nil)
    }

    func mailComposeController(_ controller: MFMailComposeViewController, didFinishWith result: MFMailComposeResult, error: Error?) {
     
        switch result.rawValue {
        case MFMailComposeCancelled.rawValue:
            print("CANCELED")
         
        case MFMailComposeResultFailed.rawValue:
            print("Failed")
         
        case MFMailComposeResultSaved.rawValue:
            print("Saved")
         
        case MFMailComposeResultSent.rawValue:
            print("Sent")
         
        default:
            break
        }
        self.dismiss(animated: true, completion: nil)
    }

    override var prefersStatusBarHidden: Bool {
        return true
    }
}