So today I required a micro sim card for a phone I had purchased online and decided to facilitate this through the local T-Mobile store. In the process of doing this I learned that I had been sent to collections over an $8.04 outstanding balance from two years ago. Essentially what happened was when I requested the sim card change they told me my account had been cancelled and I had been sent to collections over this charge. After about 20 minutes of them playing phone tag and me requesting information, when I finally asked when the account had been cancelled they informed me that this had happened in 2012, and they had been looking at the wrong account (subsequently they were able to give me a new sim card and send me on my way... with a phone number for a collections agency).
My question is as follows: Two years ago I switched to a no contract pre paid plan and closed out my old account. I kept the same phone number and the same online account that I had always used. My balance was paid out to zero (to my knowledge) when I made this switch. I never received any notification from the collections agency or T-Mobile regarding an outstanding balance. Apparently my credit score has taken a hit over a balance of $8.04 (which I just paid out though probably should have disputed) which I was never notified of. T-Mobile has my address and phone number - how come I was never notified?