Keep getting hang-up calls from them.

This company has been calling me for a long time every day, at least once sometimes 3 - 4 times very hour. If answer machine is on they call and wait for 30 seconds then hang up. There is never a human being saying anything even if I answer.  I looked the number up online that is how I have any info at all. I see some say it is Direct TV, which I have never had, some say it is a medical bill collector, of which I have none just going thru bankruptcy last year. This is crap and somebody should stop this continual harassment to the public.