FNB BANK WORST SERVICE EVER

THE WORST SERVICE EVER!!!!!!!! Thank you FNB Collections department for the worst service ever. I have an arrangement with you people to pay my credit card off with x amount every month. You have just debit my account for over R8K. Please tell me how you are legally aloud to do this when no one from your department contacted me to inform me or authorize this with me? You just went ahead with this. This has now amounted to the fact that I cannot pay my rent, purchase food or fuel for the rest of the month or pay my other debit orders. Who do you think you people are? How about you phone or email your clients and inform them of what is going to happen? Please ensure that you refund this amount ASAP or this matter will be taken further