Xfinity Mobile Promo

I added a mobile line to my Xfinity account in October, it was supposed to be “free” for a year. Except every month I have gotten a bill for $40 plus tax. Every month I call customer service and they credit my account and tell me that the issue is solved - but it keeps happening. I called twice about my December bill and they keep saying they’ve credited my account, but now I owe $51 and my account is past due. I tried activating the Peacock Premium benefit that they offer to watch the Super Bowl tomorrow but since my account is “past due” I am unable to. 

This has been an incredibly disappointing experience. I’d rather pay for my phone service somewhere else than be lied to like this.