I think it was an extortion or one of those calls that asks you to put money on a pre paid card but they hung up when I told them I was not the person they mentioned.  A woman called and asked for a person by name and she said it was a family member from out of state but never identified herself by name.  She kept on saying "oh come on aunt *Person by name, I am your niece from out of state"  I told her to identify herself then she asked me if I was that person, by this time she had changed her tone of voice with a more serious and I said I didn't know who she was unless she identified herself.  She hung up.  Never asked me if I was not the person could I please pass the phone to her "relative".  On the phone, the name appears as unknown.  What this person doesn't know is that I am the person she asked for by name but I don't have any relatives living out of state nor do I have any nieces AT ALL.  That is why I think that was a scam and it was probably done with a disposable phone.  It is scary that any extortionist can get your name and phone number even if you have it in national block.  I doubt the FCC will ever do anything to these criminals.