Im in shock and disbelief

African bank has done it again, last month I was called and advised that I owe an installement that did not go off a year ago, after demanding answers on how such a thing could go unnoticed, I was advised that even though I have a debit order, its my responsibility to pay...thought that was what I was doing by having a debit order! I demanded answers on how I was not contacted, and how a payment could be missed for a whole year, essentially causing harm to my credit record, and now im being notified, the consultant just reiterated that its somehow my fault that THEY did not debit the account, I finally relented and told them to debit my account for my new installment as well as my arrears amount, and asked them to confirm that, that will be that! I was reassured that once the debit is complete, that concludes the transaction, my account was debit on the agreed upon date, along with an additional 500 and some change for the arrears amount. I should have know if they can be *********** enough to not see they werent paid for a full year, that this would not be the last I would hear from their stupidity. THIS MONTH i was contacted again, and I was advised that I still owe an arrears amount, from a year ago, naturally I flew off the handle, explaining the above, I asked how this is possible and what is the amount, it was R100 apprently not paid from last year, the month after the previous arrears transaction, I asked if this is the case, also, my installment is alot higher than R100 why did the multple people I spoke to last month, not tell me anything about this, because then I could have paid 600 and some change instead of the 500, which would have by what they are saying should have concluded my business, which is exactly what I said before. Being unvelievably irate, I asked to speak to a manager. The manager then proceeded to advise me that I am still liable for the R100, despite the various incompetence and errors made, dispite the fact that no one told me this last month when they initially called me with this ubsudity, despite the fact I had them debit me and asked for the exact amount of arrears, he just calmly explained to me that he will listen to the call, but it does not change the fact that im liable for the R100, now I can easily pay this money, that is not the point, where is the faireness towards customers, where is the protocols that safe guard customers and how is it allowed for a business to cause a customer this kind of aggrevation and then just politely tell you oh well, you are still laible, an agreement was made, that I took out a card, I use the credit, and you debit the amount on a monthly basis, that was the agreement, and I have no problem paying what I owe, but you can not tell a customer that we did not do our only job which is to debit you, and then we are telling you 1 whole year later after we have ruined your credit history and you didnt even know why, and then we force you to pay extra money, promising that that is the owed amount, then call you a month later saying oh well, our agents ****, and you infact owe more so pay us now again, HOW IS THE CUSTOMER BEING TREATED FAIRLY? Arent there any laws against these incompetence? When I asked the manager when I can expect a call back he asked why he would need to call me back, I asked if there will be any investigation, and surely customers cant be treated this way, he reiterated that he will listen to the call but he will not make me privy to that information and I am still just liable for the money, I asked how I can be sure this wont happen again, he said thats the amount that must be paid. YET LAST MONTH I ASKED TO PAY THE FULL ARREARS AND YOU GAVE ME AN AMOUNT AND TOLD ME, THAT IS IT, now im supposed to trust that you are telling the truth this time, and wont harass me for more money next month, im in total disbelief that a bank can not keep track of what customers owe, and cant give customers accurate information on what they need to pay, does not debit customers when they are supposed to, and if the debit doesnt go off, DONT WAIT A YEAR TO SORT IT OUT OR INFORM THE CUSTOMER. This is unbelievable, surely they can be reported somewhere for unfair treatement to their customers. Naturally I was very irate and was all but yelling over the phone about this compelete injustice, and the manager was more annoyed with me about how im now treating them, but they are somehow allowed to harrass me for money every month, yet never give me accurate amounts.