Capitec bank with permanent default record policy

Almost 20 years ago l defaulted with Capitec account and discovered later that the account was sold the time l wanted to settle. The company sold to later told me the account was written off and as a result l am unable to settle. The sad part is this is still reflecting on my Capitec savings account immediately l visit a Capitec branch for my savings account related issues. I don't know the solution to this matter. I desperately want to clean my profile with Capitec but l am refused by 20 years ago mistake. What kind of bank is this. A mistake of my youth is still haunting me even today.