They have only one weakness and that is the fact that you know they are going to keep calling you. The numbers they are using evaporate as soon as they hang up and there is apparently no way to trace them or block them. Your only defense is to turn it into a hobby. Go to Walmart and buy an air horn from the boating department. Set it beside your phone and just wait. When they call, and they will, press 1 to speak to a rep (not sure if that stands for representative or reptile) but when they answer try to blow their eardrums out the other side of their head. Soon you will be looking forward to their calls. It's great fun.