Columbia University Program Assistant interview questions

I interviewed for a Program Assistant position within a program at the Mailman School of Public Health. I had two interviews, one of which I got word of the day before, and also was asked to complete a writing exercise. The writing exercise was supposed to be the final task after which they would make a decision and I was told I would hear back soon, however I never heard anything, even after I emailed a few weeks later and then called and left a voicemail a few weeks after that. I understand if they gave the position to someone else but I don't know why they couldn't be bothered to tell me either way.