Associate, Transaction Opinion

I applied to to the position at the end of June and received a call from HR on June 30. It was the basic phone screening of resume , etc. The TO group has 5 members, and I had either a phone or WebEx interview with each - 1 associate, 2 VPs, 2 MDs. I felt that each went well and that I was progressing along in the process. The last day of July my HR contact called to schedule me to fly to the office for an onsite, then accidentally copied me on the internal emails with her colleagues. I saw that things we going well and that they wanted to move quickly. 2 days later I received an Email that they were going to slow the process down. I reached out once per week for 3 weeks and received no reply. On September 10 I received a boiler plate rejection email.

TLDR; after multiple interviews and being strung along told that I was a top candidate, I was ghosted for 3 weeks and given a form-letter email rejection with no further explanation. Completely unprofessional.