It also does little to stop collection agencies, and of course scammers have carved out their own little "exemption", known as the "catch me if you can" loophole.
Based on described behavior, I would tend to suspect one of the above, rather than a "charity". Of course, charities which cold call, and scammers, are frequently one and the same.
This number called my house 4 times within 20 minutes! They do not leave a message and when you call it back it tells you that the mailbox is full. I would think that there's a way to end these ridiculous, irritating calls. This is the second number that's doing this. Verizon does not know anything about them and can't stop them.
I'm so glad to find out this is happening to other people. This number is also calling my house non stop. Sometimes back to back, its really strange. We're going to call the phone company and try to find out if the number can be blocked.