Anduril Haskell Software Engineer interview questions

I applied to a UI job, but the recruiter got back to me and suggested I apply for their haskell backend role. That sounded good to me so I did so. I did the first technical interview, and did great. I went onto their third round, which was four back-to-back interviews. First reviewer was 15 minutes late. Second and third interviews were technical, and again I think I did great. Fourth interviewer had to cancel. Recruiter got back to me and said I failed the technical. I asked him if he had anymore detail as to why, and he said he would ask the team and get back to me, and then never got back to me. I thought I did well on the technicals because I completed the challenges, and the interviewers themselves seemed to say I did good. I am pretty confused as to what happened. Oh well.