Same deal. They called to access my computer in order to refund my money in which there is no refund to pay.
Once in, they lock me out of my computer and which now I have no access.
Then instead of refunding my money they wanted $500 to fix the problem they had created.
Usually the phone number shows up on the display " unavailable "
The number *******0000 is not a valid number. They just called me on a *******569 which connects into a new voicemail that is not set up.
Whatever you do never allow them into your computer.