Called and hung up with no message.

Got a call, no message left.   ???
I called then back and got a recording that said, "Thank you for calling. All of our operators are busy.  If you wish to have your number added to our do not call list, press..."

Same thing. Got a call, no message left. Called back, got to automated message machine 'all operators are busy, if you wish to have your number removed, press 1'.

Health insurance scam artist

DItto got the same thing