just got a call, missed it and called them back from the aller ID information.
"number does not exist" says the telephone company's automated system.
isn't Caller ID spoofing illegal?
Yes, for the most it is illegal. However, there are some measured exemptions. Law enforcement, Private detectives, bail bondsmen, and unfortunately debt collectors, can use spoofing to a limited degree. Just another hole in the government's system of allowing certain considerations to its chosen few.