Unhappy FNB client

I am so unhappy with FNB, on Saturday an amount of R954 was debited on my account without my knowledge then my card declined cause I didn't know it didn't have enough money for the transaction i was very stressed when i asked what happened they told me the money went into my savings account and there was nothing on my my savings account. The following day it was on my savings account then I was charged fees for the card declining, how can you charge me fees for something done by you? then today when I go to my App there's amount of R50 for item paid no1 i don't even know what that is and I've waiting for answers still nothing. FNB is now ******** it's customers how can you deduct money from your clients account without their knowledge, your fees are already expensive, I have a cheque account but I still pay for many transaction fees and I am so tired I will be closing my FNB account.