Awful billing practice

I am so disappointed over the integrity and empathy of AT&T. I ordered a new Apple Watch January 2019. Been paying my bill and been up to date with everything. We are in January 2021. Never had any issues with ATT love the service and I thought hey I should get internet service with them as well. Well I was unable to get internet service because it stated I owe $229.99 I would have to pay that. And I contacted customer service. Turns out I had already been sent to collections. First I spoke to Cedric who escalated the issue. After being in collections for two years! They contacted the collection agency and supposedly removed my account from collections. Cause it should of not been sent there. But they still want me to pay $67 because when the Apple Watch was purchased it was on its own account. In March 2019 it got moved to the same account as my iPhone. So the balance for those 3 months never transferred. Because they opened a new account. Two years later after sending me to collections, messing up my credit, they still want me to pay. Even though I was not aware I had a balance. I spoke with Cedric, Brandon and finally with Ebony. Ebony is a ‘supervisor’ I was told yes the amount that was sent to collections was a mistake but still want me to pay $67 because those are valid charges. Even though it was not my fault that I didn’t know I had a balance because they never carried the balance to the new account that was created. I have been going back and forth with ATT all day! Last person I spoke to was Ebony and I still had questions she placed me on hold and after being on the phone for 2 hours she hung up the line. I understand if the charges are valid. But really ATT after messing up my credit still want me to pay $67. Worse customer service by Ebony. I asked to speak to someone above her she denied it and hung up on me