Paid debit orders

Hi, i am very unhappy with fnb that takes my money, always leaving my account in a minus, everytime my debits need to be paid they add, items no funds paid, I left no money in the account yesterday because I don't have money to pay my debits this month so fnb allowed my debits to go through, which leaves my account into minus now, I didn't give fnb authorisation to pay my debits cos tomorrow they will add items no funds paid, fnb makes me broke every month, cos I must pay for stuff and fees I don't know nothing ablout, I am closing my policies with them and my account, I had enough