Unauthorized DebiCheck

On Sunday 31 January I was debit R89.99 by an unauthorized debtor. I have been receiving this debit or der for the past 3 months and have been reversing using the banking app. This time however I was not able to reverse it. When i call the call centre i was advised that it is a DebiCheck debit order that i approved (something that i didn't). So basically i cant reverse the debit order and it will continue debiting forever.