Lack of communication

I would hereby like some clarity from SARS with regards to the money they claim is owed to them by me without any valid explanation or clarity.

According to me, when i resigned in 2016 the money paid to me by my employer was taxed and settled all the other outstanding debts from SARS and I am shocked to find out I still owe SARS. I would like to get some clarity and understand what is being owed by me and how. Kindly assist