Unauthorised Debit orders

Debit orders went off again on my account without my consent. I have never instructed anyone to debit my account on Saturday 8 August 2020. When I wanted to reverse the debit order on my FNB APP no debit orders were reflected. I also disputed the debit order on my app but no reversal took place. I want my money back. FNB bank secure chat is also of no assistance.