Ridiculous bank

I have an active card with this so called bank (African Bank) i took this credit card last year 2016 and i have been paying it without fail with a debit order payment option and they are always number one to go to my account and take their money (installment). last week 4th October 2017 got a call from their collections department stating that my account is arrears and there are months where i reversed the money that has been debited. my question is why were they quite all along. and to my surprise i logged in to my account there was a - R 615.14 after few hours i logged again there was R 585 some change, i have asked my statement of which its not clear and asked to be called by on of the Supervisors but i haven't got a call from the. Proving that they are ****** i paid 1200 last week but the balance is still the same. It either i get proper clarity or i stop paying these idiots nxaaaa. I am so tired of this....