Amgen Senior Associate - Commercial interview questions

Got interview process had 5 interviews, first with one hour duration and the rest with 30min. Feedback from each was very quick and all where set up in a space of 2 weeks. Constant communication and feedback which was nice. Offer pay was not adequate to senior position and for the project scope and challenges so rejected the offer. They were not flexible to counter offers saying that was “already in the top of available budged”. Although benefits were in line with what the industry offers, the salary is definetly lower considering it’s a senior position.