Unauthorised debit orders

For months now I have been battling with unauthorised debit orders on my FNB transactional accounts. It has now become a routine to visit a branch to have these debit orders reversed. This morning I woke up to three debits orders (R99.99, R69.99, R89.99). Whenever I try to reverse these I am being told that these will incur a penalty or charge. I have instructed FNB to block off these debit orders. Perhaps I should move my account