Absolutely ridiculous negative steps taken by Nedbank

I had the worst experience I can imagine at Nedbank! If my home loan wasn't with them I would leave them immediately. I needed to pay R25 for debt on my credit card, paid R5 000 four days late, and they subtracted 15% from my 100% credit worthiness and sent it to ALL credit companies! This has the bad results that I cannot even get a Telkom contract for a low amount! I contacted Nedbank and had a e-mail discussion with them about this matter and asked them to reverse this. With a very "numb" language they just say no. How ridiculous can this be? I absolutely would not recommend them to anybody. My son had huge problems with them as well, without ANYTHING from his side he had no access to his money AT ALL for 2-3 weeks! Apparently because he was born in Zimbabwe as a South African with a South African ID and birth certificate from the beginning!