FNB not sticking to the agreement

Sometimes its useless to call FNB as some of their agents have no clue of the products being offered to their clients , apparently FNB has been taken my money saying its for charges , tried asking the agent what charges she said she doesn't know ho to explain to me , How can i be charged such an amount , can someone call and explain this , That's the reference for my call i regret talking to her as she seemed she doesn't even want to assist me Rw***