public async Task <ActionResult> Add(InterviewDTO interviewDTO)
        {
            interviewDTO.SalesPerson = await _salesPersonService.GetByNameAndEmailAsync(interviewDTO.SalesPerson);

            var company = await _companyService.GetByNameAsync(interviewDTO.Company.Name);

            if (company == null)
            {
                company = await _companyService.AddAsync(interviewDTO.Company, true);
            }
            interviewDTO.Company = company;

            var interviewer = await _interviewerService.GetByNameAndEmailAsync(interviewDTO.Interviewer);

            if (interviewer == null)
            {
                interviewDTO.Interviewer.Company = company;
                interviewer = await _interviewerService.AddAsync(interviewDTO.Interviewer);
            }
            interviewDTO.Interviewer = interviewer;
            var interview = await _interviewService.AddAsync(interviewDTO);

            foreach (var fairId in interviewDTO.FairIds)
            {
                await _interviewFairService.AddAsync(new InterviewFairDTO
                {
                    Name      = "GörüşmeKaydıFuar" + fairId,
                    Interview = interview,
                    Company   = interviewDTO.Company,
                    Fair      = _fairService.Get(Guid.Parse(fairId))
                });
            }
            return(Ok());
        }