They keep calling my business number but never leave a message or hang up when I answer.

The call from different numbers like this one they are persistent they don't not waver . It's some sort of scam I can't figure out yet.

I have been receiving these calls from this number for a few months. When I answer -there is a recording that makes no sense and then it hangs up. When I call back to request to be put on "the do not call List" the number is disconnected. Whatever. Some  sort of scam no doubt -unsure of what the point is. Will now simply block this particular number.

Called me ....didn't answer never leave no message.