FNB ZERO SERVICE

I have now on 2 occasions raised an issue with FNB where a transaction was duplicated on my account and in so doing i communicated with the merchant as well as with FNB. Following FNBs instructions to show proof i have communicated and showing proof of the duplicate transactions and to have one of them reversed i have now been asked again to submit proof of my interaction with the merchant WHICH i have already.

What more must i do to get the duplicate transaction reversed as this was done IN error. No one from FNB has contacted me in order to provide context, instead it seems the SYSTEM generated protocol and process is followed instead of the human element here. This is highly frustrating to have to go back and forth like this.