Interviewing a financial company, first of all, the face of the department, passed the interview of HR manager, but failed. What is the reason?

It's simple. Maybe people don't want you because they think your background and experience are good. They may prefer fresh graduates, which is easier to control and less likely to change jobs.

There is also to consider whether the salary you want is higher than HR's expectation. HR needs to see if your salary is in line with the company's profit to a great extent. If your asking price is higher than HR's expectation, you will definitely not be taken.