Unprofessional and undignified - IT Engineer Brevan Howard Employee Review

I went through several rounds of interviews, and a few hours before the final interview, which I'm told was more of a formality, it was cancelled with no explanation. Then a few months later the same role was advertised again, and I found out the same thing had happened to another candidate when I was being considered. I was also told they weren't interested in interviewing previous candidates. It was very bizarre situation and incredibly rude and unprofessional.