Arcesium Senior Software Development Engineer (Senior SDE) interview questions

Contacted by external agency and scheduled hackerrank test. After that had one on one discussion with senior manager. Once clear that, had 3 back to back interviews with team members on system design to hard level DS/Algo. Got the feedback from agency that cleared all the rounds and final round will take place with HM on some date. Didn't get any response from arcesium on HM interview date. Asked agency for the next round they said your feedback is negative they got confused with some other candidate. If they can get confused with senior-level candidates you can imagine how much confused their team members and senior leadership would be. Total waste of time and energy. Luck matters a lot in arcesium. Don't throw out a party until you get a complete offer in the mail. This could be possible that after sending they might say "Oh!, that offer was not for you we mistakenly wrote your name on that, please discard". This would be very rare so do party after 3 4 days of offer letter after repeated confirmation from HR that "Yes, this offer is for you only"