Four rounds of interviews with the senior engineering staff. Got the offer and down-levelled. I insisted for the role initially offered, the HR setup an additional round where the down-level offer still stands after this additional round. The additional round was a take home architectural challenge. The interviewer was not happy with me, felt like they were trying for the same position and it was a conflict of interest. Got rejected and they rescinded the offer, including the down-levelled offer. Wasn't professional at all