BD Senior Manager interview questions

Hiring manager contacted me based on referral from a former person I supervised. After a 30 minute phone interview was asked to come in for 5 one hour interviews the following week. Interviews went well but I was left in conference room with no contact information since last interview was on phone with west coast. Admin that set up interviews was out that day, I walked myself out to front desk in a secure building. I sent thank you emails and only HR and Sales person responded. They did not make any contract until 6 weeks later was asked to come in again. Met with hiring manager's supervisor and hiring manager again. He told me to expect an offer the following week. After another 6 weeks, I reached out to hiring manager and no response. Never followed up with me again.