You *CANNOT* get off their list by kindly asking them to remove your number, or using their automated systems to do so. All that does, is tell them that the number their auto-dialer just called is is a valid, real number with a live person that will answer it (you). That's what trying to remove yourself from their list does in all cases of illegal and /or scam companies. Instead, either don't answer (only slightly better, but better), or use a voice service like a VOIP service or Google Voice to block the calls. Better yet, someone who has time to deal with it could report these unsavory characters to the FCC and ensure they follow-up.
Just got a call from them. Gave them the "Number has been disconnected" recorded message. Don't know if it will help or not, but I've tried do-not-call registry, call block, call forwarding, everything except automatic call screening and nothing has helped so far.