help with erroneous billing on my sons account of which I have POA and am slated as an authorized user on the account by xfinity

Last October we switched the account speed and closed the NOW account. We are still being billed for the NOW acct and have been since Oct., as well as being charged for the newly opened account. You are double dipping and have no authority to do so. I am really ready to go to Consumer Protection. We were also quoted a price of $40.95 per month for xfinity internet and you are charging $50.95 per month. And yes you are taking it out of his checking account so there should be no extra $10.00. This all started by wanting to correct the spelling of his last name!! I have spent over 20 hrs talking to India, Philippines, California, Mexico, Texas etc. and no one is able to help me. This is ridiculous!!! I've also been suddenly disconnected or should I say suspiciously disconnected with no callbacks which were requested. Even after escalations. This needs to be addressed by a human being that can help and not a bot asking the same questions over and over and over and over again which have no pertinence to my problem!