How can a block a cell phone number on my Pantech Ease?

I have a At&T Pantech Ease phone. There's this one stupid survey person from some company who won't stop calling me. So I played around with phone for a while, and I couldn't find a feature to block phone numbers, so is there any way to block a Telemarketer? I tried something that I found online that said to call: *60#. Which didn't work, it said "Not Supported", so is there any way that works to block this number?