ADITIONAL AMOUNT WITHOUT MY CONCERN

On the 11.02.2016 I got a message that an additional amount of R332 is going to deduct on my account on the 15th and according to my agreement with African bank is to deduct instalment of R1346 for loan and R617 for credit card and the arrears I told them that I will reduce it as soon I see that I have available money, but they add additional amount without my concern and I called them they told me that they don't see it , but I got an sms. I know I owe them but I also know that with my budget I cant and if they deduct that amount it will affect my bank account and it will make me reverse the amount and which means if they want to play like this they wont get anything from me.