Arrears and bad service

I just called African bank to check the status of my account, only to be told I have 601 arrears from Nov 2014, I have been receiving statements from African bank every single month , and this amount never reflected. I asked the *********** agent that was suppose to help me to explain to me why the rears only subside now- 7 months later. I have called the customer care more than 4 times in the past month doing a status check on my acoount not once was I told I am in arrears. I have also increased my limit in nov /dec 2014 and was never told of any arrears. 7 months down the line you tell me about arrears from Nov, I need some one who is not going to hang up on me when I ask why and where do the areers come from. and why I was never notified until today. I called the call centre at exctly 16:36 and a guy by the name os Sakhile kept me on the phone for 15 minutes only to hang up on me when I asked where the arrears come from...that is down right rude and unprofessional, Its money we talking about and if I am liable I need to understand before I pay what its for. Not hang up on me and still expect me to pay. I pay for the things I know and understand.