Apple Watch promotion promised and not applied

As the 17pro offer came available with the preorder, my husband and I switched over to Xfinity from t mobile. We went to our local store and were advised we had an additional offer of getting two  apple watches at a minimum cost for my husband as he wanted the 44mm, in which we were advised would be an additional $4 a month.  Mine to be 0. See second bill online, no watch offers applied. Contacted customer support and was advised $30 credit applied however to continue the discount I would have to contact Xfinity once a month… is this true? How can I get a permanent resolution? If I knew I was paying for the watches I wouldn’t have gotten them!!