AT&T Internet 300 Free Gateway for Online Orders - Holidays Offer

I placed an order online for AT&T Internet 300 on Dec 19th 2020. There was a promo that stated that the gateway is going to be free for 12 months and after the 12 months the standard $10 equipment fee applies. The promo also showed up on my cart as a separate line before I placed the order. 

My first bill got generated I got charged for the equipment but I do not see the promo applied. When I contacted customer service they were not able to see the promo on the order on their end. 

The order status page doesn't show me any order details like other websites and unfortunately, I did not take screenshots of the offer nor my cart. Did anyone else face a similar issue?