TIAA .NET Full Stack Developer interview questions

Almost waste of time, I have applied through recruiter REISHR. First round was fully technical for an hour. Second round was MR Round about projects and working style and little Techincal. After MR Round they take Again technical round and even though we tell interviewer that we have not used specific concept till the asked questions on same thing. Though your interview is went well they rejected without any reason.. and you will not get reason because you are applied via staffing agency. Dont attend the interview, just wasting our time for 3 days. Interviewer is having lack of knowledge. Even though you have tried something at your own for 8 years they try to force that your are not right..