Debit order dispute (*****)

Nedbank is pathetic I have been getting unauthorized debit orders, when I call in I was advised they can't reverse them as they've been deemed as mandatory, by whom I don't know instead of rectifying the error I'm issued with a number to call and advise the so called company to stop debit ting my account, the consultant said I should open a case with SAPS, the nerve, who's responsibility is it to secure my funds?

It's been 3 weeks now and nothing is done