NTT DATA Sr. Consultant interview questions

Interview process was very well arranged.I was called at NTT data office and gave two technical rounds.Both technical rounds expected to know - .Net framework,design pattern,ASP.Net, Entity framework etc. The rounds were telephonic with NTT panel and client. Its was moderate in terms of difficulty and well managed.After the technical rounds I was called to different office where I was put through management round.Once done, HR called me that I have been selected and salary was negotiated. I was in conversation with HR from Bangalore, who said I have been selected and asked me to not accept offer of any company as I was already holding multiple offers and they are about to release offer ASAP. He kept calling me every week to make sure I am still inclined to join NTT and always assured me that offer will be released at earliest and I should give negative response to other company.I waited for 20 days but no offer was released and when I called them back, he informed me that the offer is not getting approved by Hyderabad management team and whether I am willing to relocate to different location(Bangalore)?. This was really very unprofessional specially when HR assured me that I will receive offer at any cost and advice me to refuse other offers. Its really very disappointing to see the poor management of esteemed company like NTT.

written,tech F2F,HR then client round where again 1 tech then 2 tech then again manager round after that offer letter then joining after 3 months of my NP 1 tech then 2 tech then again manager round after that offer letter then joining after 3 months of my NP