FNB Merchant Services

So this morning I wake up to see an amount of R402.50 debited from my account for a Speed Point Device that I don't have. When calling business banking they indicate that i have to speak to merchant services . I get transferred and this takes up about 20 min with verification, etc and getting to that section. When getting to Merchant services and explaining my problem , I was told that he can't assist and would have to wait until Monday when finance is back. This is totally unacceptable. So Basically when money is debited from your account then they can only tell you depending on what section took the money from you. It is not like it is a 3rd party who took the money, it is FNB itself.