If you have the right place, a good way to get back at them is to color some paper black, put it into your fax machine and loop it back together.  Block the phone number and let it fax all night when no one is there.  It'll run their paper and their ink out, and even after they refill it the stuff will be in memory and print.

Getting this too and called them back from my work number and it's either Frank or Mike Jones and his mail box is full. Next time they call i will answer and continue working and they'll just hear typing in the background.. I also plan to block the number.

Credit card services. Trying to get your credit card number. SCAM.
Report call to the FTC at phone # 877-382-4357

this number keeps calling but they never say anything when i answer.

These people are awful. They keep calling and like others have said hang up when you ask to be removed from their list. The call I just received sounded threatening..."this is the last call you will receive to resolve..." (I wish), "we sent several correspondences to your residence..." (don't think so). They are trying to make it sound like you better to talk to them to resolve a problem but really, they are the problem.