Block Compliance Program Manager interview questions

HR is based in the US. Initial screening call with HR rep, explaining the interview process, salary expectations and q & a. Provided upfront salary expectations & was advised they were looking to offer 20% less, however they would review this as they were getting consistent feedback their salary offer was probably below market rates. On this basis I agreed to proceed to interview stage. This involved 3 rounds of interviews with multiple people, involving 6 people all up. All the people conducting the interviews were lovely and seemed well versed in their respective areas. Culture and people is an important aspect to understand through the interview process, with the Melbourne office seeming to have quite a supportive and inclusive one, thus I continued with the interview process. Completing the interviews culminated in a final discussion with HR to get direct feedback and to confirm whether a consideration of an offer would be accepted, given the successful completion of interviews. Which I said yes to. HR then went on to state the salary of the role, which was now even less than the original salary they had indicated. I said hold up, I had clearly stated my salary expectations at the start of the process, which HR responded "We don't negotiate". So HR totally mislead me from the start and I wasted over 4 hours of my time in interviews and even more in setting up the interview dealing with a HR who really didn't care over a whole month. HR is devolved from the whole process, and have wasted probably multiple candidates times and internal people's time to go through their multi round robin interviews. Given the time invested, a generic unsuccessful email was sent, with no explanation. I sought feedback, in order to help improve in future interviews, however again a generic response was received with a more suitable candidate was found. So warning, unless it ticks off everything right from the start, go for it, of not, don't waste your investment and time.