RTC Agency interview questions

I had a brief phone interview and sent over writing samples. I was told I would hear in a week whether or not I would advance in the interview process; however, no one ever reached back out to me. I reached out to HR multiple times via email to see if they were still in the decision making process or had decided to pursue, but I was not even afforded that courtesy. They never responded. EVER. Not only is this maddeningly frustrating--it's unprofessional. Some ad agency.