exact same thing happened to me. Annoying - when you answer and tell them they have wrong # , they hang up.

In the last 48 hours, this telephone number (along with several others) have called my government issued work cell phone over 20 times.  They never leave a message.  I picked up one number yesterday and when you answer, it rings through to a switch board where someone who barely speaks English answers.  If you ask them to remove you, they simply hang up the phone.  This is infuriating!!!!!!