It's a pain to have them call 2 or 3 times a day for the past 6 months.

I have had them call me for about 6 months now.  Would like to know who it is, but I hate to get the phone when it's not a number I know.  I do the same thing and let the machine pick up and they hang up.
I hope something gets done about it also.

call came in, caller ID showed it to be "Pub Saf Inc"

let it roll over to answering machine, and as soon as the machine answered, they call got disconnected.