Unauthorized debit order issue still not resolved

Last month I noticed a debit order with a strange amount. When i called FNB i was given a number to call which i did contact and they said the company's name is Stokvel Direct and they debited money from my account without my permission, in fact, I do not even know who they are and what they are about and the worst part is that I cannot even reverse the money because it doesn't show on my debit orders but on my transactions. I have been phoning here and there but I have not had any joy and I know that it is not FNB that debited but surely Fnb should be able to protect their clients from this. I have been banking with FNB for many years but I will have to resort to closing my FNB account and go to another bank if they cannot assist me with this as I cannot keep having debit orders I do not know of, this is hard earned money for my family and I cannot let ********** do what they like with it. Please, can you intervene and assist?