Nasty problem...
On a landline?
It is/was actually a problem of AT&T not keeping track of where and to whom they assign numbers in rural areas-after screwing with it all day and threatening to sever my 30 year relationship with AT&T, cancelling service for both my cell phone and landline, they got with the program-but if I had a dollar for every inappropriate thing I said, or time I shouted at someone yesterday, I could afford an operational furnace for this place...