Horrified with Nedbank

I opened an account with Nedbank two weeks ago, for the sole purpose of being able to manage my home loan that I have with them. Since then a debit order was set up (without my consent) by some company (I haven't got a card or given my bank details to anyone) so I have no idea how this was done, and Nedbank don't either. But they are charging me to reverse and stop this debit order and are making it my problem to follow up on and resolve. All the while charging me fees. This is shocking! It also happened to my husband, so I know it must be a common occurrence and most people are probably unaware.