Disappointed FNB customer

I've been a happy FNB customer for the longest time but that has suddenly changed! The fees are ridiculously high and to make matters worse, how u have a revolving loan under my name which I cannot afford to have. I want it cancelled immediately without obligation to pay the interest or service fees since I did not use it. I was going through the offer on my fnb app when I accidentally clicked accepted before I could even read the pre-agreement. The system should be designed to ask a person if they confirm and not deposit funds into their account without reading the pre-agreement or confirming. I have tried to contact you telephonically without success! Please cancel this service!!