They are a debt collector and have called from 704 area codes..I have vzw service and u can block up to five numbers for free...so they have started using a second line so I blocked that one too.
They keep calling and when I pick up they hang up. If they are collecting then they have to at least answer the other end to find out the number they are calling is indeed the correct one. They should have a choice to advise them if they are calling the correct person they are collecting from.