What are private bankers for again?

So here I am again with FNB. I Declined a transaction in my banking app, but it still went through, the vendor has subsequently taken additional amounts not authorized by myself.

FNB private clients takes forever to get back me and then tell me they can't help me, I must contact the vendor myself, which I'm supposed to find where, I might add?

I end up canceling my card on the app and want confirmation that no further funds can be deducted and then get told to phone *****, this after making it clear that I'm not in South Africa.

Tell me what is the purpose of a private banker again if they can't help you?