I usually get these hang up, annoying, calls on my house phone.  this one appeared on my  CELL phone!!!

Computer recording trying to get a response. Blocked them.

why doesn't the 'national do not call registry' stop these spam calls???

Why don't laws against bank robbery stop banks being robbed? Get the point? Honest telemarketers follow the DNC list. Honest telemarketers. You are being called by domestic and foreign criminals using high speed internet, computers and voip. They are faking their caller ID and can be anywhere in the world. Please consider call blocking by stand alone device, app, or by service provider. Unless the Government gets cooperation from foreign Government's there is little they can do. YOU, repeat YOU, need to take action.