Handed over after being provided with letter of good standing.

I had an account with Game where I had purchased a laptop many years ago. Paid the laptop off and then kept the account. In 2018 I had asked them to close the account as I had l=no longer required the account as the laptop had been paid off as well as the camera lens that I had purchased. To my surprise they never closed the account and then again in 2020 I had queried why the account had never been closed. No one could provide me with an answer. Eventually with some back and forth I then asked them to close the account and provide me with a letter of good standing. June 18 2020 They email me with a letter stating that my account reflects a zero balance and that the account is paid up. YAY. Well so I though. July they hand me over to debt collectors saying that I owe the R200 and some change. Great first Debt Collector ends up agreeing with me that I dont owe them money after some back and forth. Now Vericred Debt collectors contact me saying that I owe them R400 and some change. I still dont understand how you provide a customer with a letter of good standing and then hand them over. Like hello??? Now when I try call them they say there is nothing they can do and I need to speak to the people that they have handed me over to. Vericred now wants the letter of good standing. How much longer is this going to go on for? This is not the first time that I have tried contacting you to fix the issue. And I normally spend more than half an hour waiting to speak to someone in Collections at RCS and no one ever answers or just puts the phone down on me when I start talking.