Avantor Lab Support Specialist interview questions

They contacted me via email to schedule a brief phone interview. The phone conversation was pretty casual. I told her my salary expectations and she said the role falls within it. They email me a few days later for an interview scheduled the following week. I met with the manager at the site for a 60 minute interview which was pretty basic and easy. But he seemed surprised when I told him my hourly rate expectations and asked me if I could go lower. A week later I received an offer $3/hr less than what the HR specialist said. I asked if there was room for negotiation to even go just a dollar higher. They emailed me a new offer that was a penny less than the original. I don’t know if it was a mistake or what but I had enough dealing with them at that point. Very unprofessional and unorganized.