Tech Mahindra Tech Lead interview questions

I gave the interview 2 rounds cleared then they taken 2 more rounds from client side. HR discussion everything had been completed . I had shared all the documents. The recruiter said I am generating offer letter for you , you may need to join early. So I resigned from the organization. I followed up couple of times he always gave excuse like last stage approval is pending after that immediately I will release your offer letter. Finally he said , the position is put on hold so could not proceed. Literally very frustrating experience.