regarding overdraft favility

I noticed money was missing from my account so I went to the bank to find out what is going on. They told me my account has been overdrawn. I do not have a overdraft facility with my account. They say when you swipe with your card some notifications only show after a few days. So now I actually owe more than 900 rand that has been overdrawn. They say there is no way of rectifing this from happening again.<br> <br> What am I supposed to do about this matter?