Wanting to claim money without proving the claim

Months after I have left SA for good, I suddenly receive a mail from a company called 'Norton/Lambrianos', claiming that I owe ABSA money from a credit card I apparently haven't settled. Very much willing to pay anything that is outstanding, I asked them to please send me a statement, but nothing. Months later, similar mail, same request to please prove the outstanding balance to me, nothing. This story goes on for months and months - eventually they send me a document with one line called ''Capital Amount'' plus interest, plus fees etc.... - not a statement at all! I was about to file the case in my spam folder, but trying to be a good citizen, I reached out to ABSA to make them aware of this possible ****, respectively asking me to send me indeed a proper statement should I really owe them. Shocking news for me today: The gentleman at ABSA sends me exactly the same ****py one line ''Capital Amount'' document I have already rejected since it doesn't provide any evidence about the transactions I have apparently conducted. Not only these unprofessional people from Norton are indeed officially appointed by ABSA, the bank provides the same s**** service....I am really shocked