MVST. Senior Software Engineer interview questions

The process was correct, I had a coding challenge that I completed successfully. But after 6 different meetings (HR, exercise defense with two engineers, company CEO, team manager, the team and then two more managers) they told me I'm not a fit for the job. The reasons were weird, because their stack is my current stack. It's amazing because even the coding exercise was good according to their comments (was a full-stack project involving backend, frontend, observability, CI/CD, devops). Six interviews and I didn't get the job :(