Unauthorized debit orders from unknown group

I dint know who these people are. They are busy taking my money from my fnb acc. A whole R196. Last month i reversed and stopped it but today here they are again. I don't use recruitment companies and I don't give out my account number recklessly. I don't know why they are debitting my account. If i was registered with them, they would have called me to ask about the reversed payment. But up to now no contact at all from their side. I guess I'm gonna have to raise this up with fnb