private IEnumerable <Guid> GetPotentiallyDormantUsers()
        {
            var configuration       = _configurationService.Get <HousekeepingConfiguration>();
            var lastValidLoginHours = configuration.DormantAccountStrategy.SendReminderAfterCycles *
                                      configuration.HousekeepingCycleInHours;
            var lastValidLogin = DateTime.UtcNow.AddHours(-lastValidLoginHours);

            return(_userReadRepository.GetPotentiallyDormantUsers(lastValidLogin));
        }