Rivian Software Engineer interview questions

The recruiter reached out to me for a position that seems to be a match. The technical interview went well and I went to the onsite interview. The funny part started from here. After several rounds of interviews, the manager finally came out and tried to understand my background. Then he told me your background is not a fit to this role. I have never experienced an interview like this. I spent lots of time preparing and took time off for an interview in which the manager in the last moment told me that your background is not a fit. This is rather ridiculous to me. Please, Rivian teams, this is not how it works. You should at least let the hiring manager talk to me first before entering the final round, even first round. This is very unprofessional and you are wasting candidates' time. Although all interviewers are nice, this process is not professional at all.