I initially applied for the position in January 2018 via LinkedIn. I spoke with a recruiter, ,and was then set up to speak with the hiring manager. I believe this phone interview went well, but I can't be sure now. About a week after I spoke with the manager, I received an offer from a different company. Since I was more interested in the Order Operations Analyst role with AppDynamics, I reached out to the recruiter first to gauge their interest and see where they were in the hiring process. She responded saying "you should probably take that other offer", so I did - informally. After a series of events and misrepresentations by the other company, I ended up not formally accepting the job offer. I reached out to the AppDynamics recruiter once more to let her know I was back on the job market and still interested in the position, since it was still open.
As of now (2/17/18), that was three weeks ago, and I have not heard back from her. I also noticed that there was a second Order Operations Analyst role open, so I applied for that one on the company website, and I also reached out directly to the hiring manager. That was a week ago, and not a word from the company, the recruiter, or the hiring manager.
I understand that some fault lies with me - I did informally accept a different offer (at the advice of the AppDynamics recruiter) and explored that opportunity for a week or so. But I do feel I did my due diligence in trying to re-open a line of communication with the company, but I haven't heard a single word back. Even a "no thank you" would have sufficed. It's the lack of communication that is absolutely unprofessional of any company, especially for someone actively searching for employment.