FNB TAKING 2 WEEKS STILL NO ASSISTANCE

I am getting charged for debit orders that fail on my premier account, but I am still waiting for my complaint to be revived and finalized as I have reported a complaint to fnb on the 29th of October already and up till today have not been resolved. I will not pay for these charges because if FNB card dispute department assisted me it would not have happened. the consultant from the card disputes department is telling me to phone the merchant and enquire what happened to the debits - how will i be able to provide proof to fnb regarding this!!!? Should fnb not do the investigation and dispute? I am indeed the client. REF:***