I left T-Mobile

After speaking with T-Mobile multiple times between 611 and Tlife as well as representatives at the store T-Mobile isn't taking responsibility to their system error of prorating me 3x on a single line to a INSANE $600 phone bill for a single line. I got on through a promotion for a pixel 10 adding a phone line to my already existing Internet line. It was suppose to bring me from $70 to $160. Instead what happened was ingot charged 300 2 times for the next bill when I wasn't supposed to at all. Then T-Mobile went on to say there is nothing they can do that it was my fault. They told me my bank return the charge I have screen shots and statements of balance proof that T-Mobile took my money. So not only did I get wrongfully charged I also got that money taken out of my account and been told that they didn't take it. So basically they robbed me and refuse to fix it. I'm here to warn anyone who has a similar issue to block T-Mobile from taking absurd money if your Joining on promotion. I was with them for Years and never had this issue until recently. I'm not looking to solve this anymore as I did everything in my power so I just want to spread my experience.