XM Radio Won't stop my service, they harrass me with phone calls every single day Internet

XM Satellite Radio is horrible!  I signed up for a year with my new car.  After about 6 months, when they joined with Sirius Radio, they started having DJ's, playing commercials for themselves, which I didn't like, so I signed into their website and asked them not to autorenew my subscription at the end of the year.  My credit card number changed because of one of those "your info may have been stolen" things.  At the end of the year, XM Radio tried to charge my credit card anyway!  I tried contacting them via their website many times - they won't email me back.  Since then, they email me about sending me to collections, they call my work and my cell phone every single day!  Nissan apparently gave them these numbers, as that's the only place that has my work number.  So I went onto their website, with MyAccount, and changed my cell phone number to 555-0100.  They still call it!  My work number wasn't on the MyAccount anywhere - but they have it, and my cell phone somewhere.

I need XM Radio to quit calling me!  These are unscrupulous business practices, and basically a plain and simple rip off, as XM Radio tried to charge my credit card when I told them no, and they do not care to respond to any of my emails, including the one I sent two days ago telling them I was going to make a report here if they didn't stop calling me.  I demanded to talk to a manager about this.  Since then, I got two more recorded calls, no attempt by a manager (or actual person) to call me, or email me.

I also sent in a complaint to Nissan about this company, as I don't think they should be doing business with a company like XM Radio, trying to harass and rip people off.