Unauthorised FNB Debit Order, called 'Bank Your Change'.

Monies have been deducted from my account for months, sometimes even more than once a month. The type of transaction is a debit order, which I did NOT authorise!! This particular debit order does not have the option of deactivating it, like other debit orders! Which goes to show that it is just plain thievery from First National Bank. FNB, I want my money back, all of it.