I didn't answer this call because I didn't recognize the number. I tried to call back, but it went directly to an automated voice mail system, and once there, the voice mail said that it was "full."
Got a call from this # today. Same thing...no message, no ability to call back. I also am on the Do Not Call list. So...I called the Do Not Call Registry (1-888-382-1222) to make them aware of this situation and I recommend and ask that you do the same. The more complaints, the quicker the attention/action. Unity always prevails.
You can also FCC them. I have tried with the donotcall people quite a few times (cell and home numbers) and nothing seems to happen. Filed some numbers with the FCC and got an email that they were filing charges against the companies that own the phone number.