This scam keeps calling for one month now at least once a day.  When I block the call from coming in, they switch to a new 4-digit number (408264....).  Same "National ..." Company and each new 264- number is disconnected when I call back.  They have called me on 7 different 264 numbers now.  Latest one blocked again and I know I will get another 264 scam number calling again!  Is there anyway to stop this?  How are they using disconnected numbers to begin with or is this a bogus number?