Unresolved issue

In December of 2024 I switched lines to Xfinity Mobil with the promise of getting a free Samsung A-35 phone and a $40.00 telephone line. My nightmare started soon after when Xfinity charged me $16.00 for he phone that was supposed to be free of charge to begin with. I have to call EVERY month to get those $16.00 credit so I been calling for 9 months already and they don't fix the issue permanently. I have several tickets open and a call back from a supervisor that never got. In my last call they confused my situation several times, sending me to different people that could not fix the issue, so in my last call I was told that "the promotion dropped" and that was the reason I been charged the extra $16.00, they offered to compensate me with an smart watch but I would have to pay the extra $16.00 for 15 more months. I am tired to deal with their issues and mistakes for a phone that was offered to me for free. Incredible that a serios company like that could not resolve the issue, I don't want an old watch that they will end up charging me for.