I answered call although I usually don't when it says "Unknown Caller." Just curious on a Sunday morning, I guess.  No answer when I said hello. To see what would happen, I called the number back and got a message that the phone is disconnected. Not the first time for this type of call. Because of the number of similar calls, it is impossible to register a complaint with the FCC every time or to block every number. Being on the Do Not Call Registry is no help.