Parsons Corporation interview questions

The interview was great. Both the manager and the director were friendly and asked straightforward questions. The problem was the HR. She negotiated the salary before setting the interview date. She was very strict and not friendly, and threatened me (I mean it was a threat) that if I didn't accept her verbal offer, I would not be accepted. When I rejected her offer, she told me that I was not the top candidate (She was offering me; I didn't know how I wasn't the top candidate) and that I have to work on myself. It was a very bad HR experience.