T-Mobile USA review: Customer service promising something and doing the opposite. Unauthorized billing.

First of all, I'm not a nut, I'm educated and was with you 30 years before leaving in Nov. 2026, unfortunately my name is Karin, (pronounced "Car, in") which I believe is part of the treatment I received. This email represents total defeat and frustration from your customer service department, they are inexperienced, unreasonable, unfair, and bullies. Before I left I bought a phone, an I-phone 17, I bought it because they promised me a trade in value of $215 off the $800 price, which I paid for in full on my Visa, they PROMISED me they would credit my Visa, no strings attached, me and my 3 lines were free to go. NOT, they held me hostage on the trade in line for 40 days, told me no refund on my trade, can't have the phone back either! and have made two unauthorized charges to my bank account. To make matters WORSE, they will no longer take my call. It's unbelievable ! This isn't the first time I've contacted you, do the right thing TMOBILE