FNB...no power to stop an unauthorised debit order.

On 11 September 2020, I wrote a review on FNB and the fact that they are charging astronomical fees on returned debits for unauthorized debit orders Planet fitness keeps trying to push through my account. Now I'm asking you FNB, WHAT EXACTLY DO YOU WANT ME TO DO!, because these idiots at Planet Fitness keep loading the debit order through my account, and every time I have to pay a penalty for it. I have asked them numerous times to remove it, but they keep doing it. What is the point of having a function on your banking app to dispute or cancel a debit order but you cannot use it, or FNB just ignores it. Now please tell me what I must do to get Planet Fitness to stop loading the debit order because they clearly don't give a **** about the bank and me as a customer...