This number calls me multiple times every single day and i just ignore it but it WILL NOT STOP. It is so terrible annoying. So, today I decided to answer and there was nobody there, just silence. they hung up after a few seconds. I hope maybe that triggered something so they'll stop calling but... it's harassment.
Do not answer unknown calls and do not call them back. Consider getting a call blocking device (or app for your cell phone)-they're available online and start around $50 or so. http://800notes.com/nb/search?q=call+blockers