Rivian Manager interview questions

Interested in this company so applied for a relevant role that was found on their website. Got an email from Recruiter saying hiring manager is interested and to set up first round of video call. First round was super informative for both of us. Recruiter had quite a lot of knowledge in the department he supported (very rarely have I come across recruiters who have in-depth knowledge of the processes, projects handled by departments they support). First round was mostly behavioral questions. It was more of an interaction. Few days later, got an email to set up another video call with hiring manager. Call was scheduled for 45 mins. Hiring manager was LATE for the interview and apologized by saying "lost track of time". Was expecting a similar (to first round) behavior and some technical questions about my background. Instead the hiring manager started the interview by saying, he thinks my background was not relevant to the role. I did not get a chance to talk about my interest in the role / company. I was confused to why they even invited my for a second round of conversation. (Without going in too much details) Sensed that the hiring manager was not sure if he had full knowledge of the department, processes, projects, etc. Some of the questions I asked were dodged by the hiring manager by saying I am also new to this role. Lack of preparation from the hiring manager.