public async void SendMail(User user, string message)
 {
     var emailMessageForDeletedUser = new RequestMessage()
     {
         UserName    = user.FirstName + " " + user.LastName,
         UserAddress = new MailboxAddress($"{user.Email}"),
     };
     await _emailSenderService.SendTheUserWasDeleted(emailMessageForDeletedUser, message);
 }