People need to understand the role of the FTC.They DO NOT represent any individual consumer in any matter. When you send a complaint to the FTC, it simply gets added to an archive for possible future use by other government agencies, and you get a dandy auto reply form letter.
Your dispute is soley with your phone carrier. They are responsible for all third party billing, but it is a big hassle for them so they try to tell you they can't do anything in hopes that you will go away.
After your initial call to customer service, if you don't get satisfaction, STOP CALLING. Stay off the phone at this point and do everything in writing.
Send all written disputes via certified mail, return reciept requested and be sure to put the certified# in the body of the letter and keep a copy for your records. This method is essential as it proves exactly what you sent.
If you have done any downloads at all from your cell phone, you most likely "authorized" the "subscription" without realizing it, as they are sneaky and love to make you scroll through endless fine print.
Demand to see that proof of your alleged authorization for the "subscription" which would include date and time, etc.