Cannot open new accounts because off TFG Sportscene

In 2019 I opened an account with TFG Sportscene and back then I was a student. I couldn't pay on time back then and this resulted to my account being handed over to their Lawyers. In late October/November 2020 I managed to secure a learnership/internship and then beginning of January/February 2021 that's when I was able to start paying off my debt. I had an arrangement of R150 pm and my debt was only +R1300. My basic math knowledge suggests that the account could have been settled in 2021 but for some reason, the last payment crossed over to February 2022. After carefully looking at my proof of payments, I realized that not all R150 was being paid off but a certain amount of money was actually paying the account and the rest couldn't be accounted for.

Now I cannot open an account anywhere else and it's almost a year now since I paid up my account, It feels like TFG blacklisted me. I tried to open an account with Ackermans and unfortunately, it was declined. I again went to Sportscene to try open an account with them and my application was also declined. Can I please be assisted with this matter on where I can be cleared and be able to open accounts