public async Task ExecuteAsync(CancellationToken token)
        {
            var messages = await _appDataService.GetMessagesToSend();

            // Create jobs for single users
            if (messages != null && messages.Any())
            {
                foreach (var messagesGroupedByUsers in messages.GroupBy(x => x.UserEmail))
                {
                    // Messages need to be casted to ICollection object, because IEnumerable cannot be serialized.
                    _backgroundJobClient.Enqueue <IMessageMailingJob>(x =>
                                                                      x.SendMessageForUser(messagesGroupedByUsers.Key, messagesGroupedByUsers.ToList()));
                }
            }
            _logger.LogInformation("Message Mailing Job Finished");
        }