Xfinity Mobile Charging when supposed to have free year

I purchased new phone from Xfinity after moving in September to which a new account was made and was told I would get a free phone line for a year.  Never happened. Contacted customer support and was told they are refunding money to my account and that I would not be charged for a year. And they apologized for the inconvenience. “I have this in writing from tech support Amey” once again I’m here on November 1, and I’m being charged again so I called In and customer support told me I never should have gotten the promotion and I will not be receiving the promotion. About to get a lawyer involved.