In-home experts scam

The short version is ATT in-home expert came to our home and gave us a very good deal in September, but later ATT charged me $60-80/monthly more than he promised. When I contacted them, they claimed I misunderstood the deal given by in-home expert while I claim the opposite. When I checked the internet, there are several similar complaints about the deals given by ATT in-home-experts. Here are the details:

I enrolled in AT&T internet in September 2022. In September 16, they came to install my internet at home. Same day, an ATT in-home expert, PR316N came to promote AT&T wireless. I told him I am not interested. I was T-mobile customer for 6 years, and I was paying $140 total for 5 lines. He told me he can give a better deal if I switch to AT&T. He told me they have free upgrade of the phones, only we need to pay one time fee for taxes. He offered me $120+taxes and fees for 4 lines. I knew taxes and hidden fees can be much, I asked him what will total bill after the fees and taxes. He told me it will be $132. I asked him 3 times if there is going to be any other charge for the phones. He said no. I upgraded 3 of my phones, and paid $800 for taxes that day. Then, next week I got a bill from ATT which was about $400. I was shocked. I called call center right away. They told me there was a mistake, and they reduced my bill to $132. The transcript is attached. Then, I enrolled autopay. I assumed the bills were $132 for the past months as it should be. Now, I realized that after October, it was between $180-210. I called the call center again, and they tried the explain the bill to me. They were charging about $60 for the phones, and some extra hidden surcharges. I told them my deal was $132 total, and your agent gave me this deal. They did not accept. They imply I misunderstand the deal, and their agent can never give such a promise. For similar complaints, please make a google search. One example:

https://forums.att.com/conversations/wireless-billing/anyone-else-scammed-by-an-in-home-expert/62cf0f1f6446fe734a7eb6c4

The way I see is that I was scammed badly by ATT. They give incentives to their in-home experts to enroll as many customers as they can. During the subscription, they can say anything they want, since after you get enrolled it is impossible to get rid of it as your phones are locked to ATT. When you complain about this, they claim you misunderstand the deal.

I called call center, made a complaint at BBB and FCC. Each time, I was called by the same customer representative Michael John. I found him very rude and disrespectful. Even though I specifically made a note that I do not want to be called by this person, he was the one calling me. I asked his permission to record the call, but he did not give me.

I want either AT&T hold their promise with the deal, or I would like to get my old phones and get back to my old wireless carrier. Thank you very much for your help.