Std bank terrible bank to bank with.

I am very disappointed with std bank, I was a client for very long but they could not even wait they handed over me to the collection company with a Capital ' R 17,915.06 to date I paid R18400 and now they gave other collection company to collect again for them they are saying now I owe 2019/03/11 Outstanding Commission R 551.99 R 9,704.83 to date really I am not sure if this is even aloud and I called the bank and it seems like they don't care someone needs to intervene here std bank I need answers.