Prophix Project Manager interview questions

I applied through online. I got a call from the HR after one month of my online submission. Chatted with the HR on the Pre-screen interviews and after a week did a phone call interview with the hiring manager. After 2 weeks, I did a business case presentation of a Go To Market Strategy along with meeting the VP of the Product management. Then I was invited to another round of interview the next week. Everything went well. After that, I did not hear back from them. I sent a couple of follow up emails to the HR with no response.Big red flags in terms of lack of professionalism. Would have expected at a minimum to receive some type of response. After 4+ weeks, when I followed with the hiring manager he confirmed they opted another person.