called a business line for a fax..our number is on a do not call registry

Got a call @ 5:12am on 3-19-13, caller id info was;NETPROWA 720-685-6282 When I answered all I heard was a Beep pause Beep pause??? Of course I called it back,only to hear the same...... I also am registered on the Do Not Call List....

This number called our house at 6:20am on 4/15/13.  Didn't get to phone in time, and our message machine took the call.  No message, just beeps but didn't sound like fax beeps.  I called it back at 7:15 when I got up, and it said "The caller's voicemail box is full and no longer accepts messages."  We are on the Do Not Call List.  The time of morning was really annoying, especially since the 720 area code originates from the same time zone.  Wish I could call them back at like 3am.....

called at 630 am est   just got beeps

calling 6:10AM, no message just BEEP ....