public async Task DeleteClassroom(Guid id) { if (_classroomRepository.GetClassroom(id) != null) { var getAllUsers = _userRepository.GetUserByClassroomId(id); if (getAllUsers.Any()) { var usersCantBeDeleted = CheckIfUsersCanBeDeleted(getAllUsers); if (usersCantBeDeleted) { throw new ArgumentException("There are users with results, first delete the results"); } await _userRepository.DeleteAllUsers(getAllUsers); } await _classroomRepository.DeleteClassroom(id); } }