It is a spoof company calling itself the "Service Centre" and trying to get you to give them access to your PC. I just tell them that the police is informed and they hang up. A tedious nuisance.
I keep getting calls from 1-212-777-3458 and I am not sure why. I tried calling back and keep getting hung up on. It seems some people do not have a life and think that prank calling is either fun or profitable. Well, the joke is on them. Idiots come in all types and they can even dial a phone now. Who knew?