Sirius Satellite Radio Charged Card Without Authorization-Won't Stop Calling Now Nationwide

We bought a new car a few month ago that came with a free 60 day trial of Sirius Satellite Radio.  We never used it because all of the channels we like are on regular radio and I personally have always thought it stupid to pay for something you can get for free.   A couple of month ago I noticed that there were charges on my husbands credit card from Sirius Satellite Radio.  (We have no idea how they got his card number.)  We checked the radio in the car and we DID NOT have satellite radio service.  We contacted the credit card company and they deemed it to be a fraudulent charge, removed the charges and cancelled that card.  Now Sirius won't stop calling us.  They call 4 or 5 times a day.  We have tried to explain to them that we do not have service, have never requested service, and do not intend to pay any charges they try to bill us.  This is all to no avail.  The callers can barely speak english and either do not understand the situation or just don't care.  Anyway, we have quit answering their calls when Sirius comes up on the caller ID, so now the caller ID says the calls are from Fuji Photo but it's the Sirius rep.