Useless systems

I'm very disappointed in nedbank. I currently am banking with them and also have a 32 days nocie investment which debits from my account R500 every month.

This month they debited R1000 of which I don't even have extra money. I called to tell them monthly debit order can only be R500 and cnot R1000. And I was told by the consultant that they can't do a reversal and that the only way to get the R500 is to make notice and cash out my investment and that there will be penalties charged if I request in the next 24 hours.

My problem is I don't want to cash out the investment and it's not my problem that their system debited twice in 1 month just because the debit order date was amended. I'm very disappointed in the service I received. And would like to cancel everything I have with nedbank.