After receiving a call from this number numerous times a day, I finally answered. No one speaks up. After saying Hello three times, I finally said "This is your last change to speak up. Otherwise I'm blocking your number". Still no response. Number is officially blocked.
If you call the number back you will hear a recording that will allow you to select the option to be put on their do not call list. I hope this helps. I'm keeping my fingers crossed!
I am getting up to 10 calls/day starting @ 8am from this number. I never answer & they never leave a msg. (just like everyone else here is saying) It's been going on for weeks. I have an Android (MotoX) and couldn't fig. out how to block, best I could find was to make the ring tone silent. Something should be done to stop this type of harassment!