Where can I send a complaint before I seek legal advise.

I was a victim of Xfinity employee fraud.  They gave me an Apple i-watch as a diamond customer.  27 years with Xfinity.  After turning down the promotion twice due to a 10.00 line charge fee I didn't want to pay..The next customer rep who again wanted to advise me of the free watch stated they would wave the 10.00 per month line charge fee and the shipping cost.  No cost to me.. I agreed.  Then when i went to pair it with my older i-phone 7..well it was too old.  It wouldn't pair.  So I went to Xfinity Store and they sold me a new phone to pair.  Now I pay for a new phone,  and I am getting a 10.00 per month line charge fee.  I was told by chat customer service I was a victim of a Xfinity employee.  But I still get  a 10.00 line chaege fee.  I am going to fight all the way to court on this one.  Xfinity if you are reading this..Please have a supervisor address this issue.  Terry [Edited: "Personal Information"]  Santa Cruz CA