Howard Hughes Communities Executive Assistant interview questions

I had a video interview scheduled for 4pm on August 31. Interview was with the hiring manager. This was after two previous interviews with other people. At 10:54am on the 31st, the interview was cancelled. I received no call, no email...zero communication as to why it was cancelled or what, if any, next steps there would be. Complete radio silence. I completely rearranged my schedule to accommodate this invite - had to secure childcare since my kids were still doing virtual school at that time. If this is how they treat prospective employees, I can only imagine how they treat actual employees. The fact that this position was supporting the Chief People/HR Officer really makes my head spin. What an unprofessional way to treat candidates.