terrible service

i am so disgusted with the service that i have gotten from fnb with regards to my debit orders they have deducted an unauthorized amount from my account then tell me i cannot reverse it as due to the high reversals i cant which is not my problem ive called the call center so many times and no answer and if the agents answer the cough in your ear and dont say anything or put you through to a service rating even if you have not spoken to an agent..i want my debit reversed