Result is sent even if MFMailComposeViewController fails to send mail

@IBAction funcmail_send(_sender:Any){


    if MFMailComposeViewController.canSendMail()==false{
        print("Email Send Failed")
        return
    }

    letmailViewController = MFMailComposeViewController()


    mailViewController.mailComposeDelegate=self

    //  subject line
    let subject = String(id)
    // mailViewController.setSubject("Bug Report")
    mailViewController.setSubject(subject)

    let to Recipients = ["[email protected]" ]
    mailViewController.setToRecipients (toRecipients)

    let body=list [row_now]
    mailViewController.setMessageBody(body, isHTML:false)

    ifMFMailComposeViewController.canSendMail(){
        self.present(mailViewController, animated:true)//, completion:nil
    } else{
        self.showSendMailErrorAlert()
    }
}

funcmailComposeController(_controller:MFMailComposeViewController, didFinishWithresult:MFMailComposeResult, error:Error?){

    switchresult.rawValue{
    caseMFMailComposeResult.cancelled.rawValue:
        print("Email Send Cancelled")
        break
    caseMFMailComposeResult.saved.rawValue:
        print("Email Saved as a Draft")
        break
    caseMFMailComposeResult.sent.rawValue:
        print("Email Sent Successfully")
        break
    caseMFMailComposeResult.failed.rawValue:
        print("Email Send Failed")
        break
    default:
        print("Email Default Case")
        break
    }

    self.dismiss(animated:true, completion:nil)
}