FNB strikes again

FNB strikes again. I opened a small business account with them to keep my sideline business' account seperate - end of the month I get close to zero but my card still works and payments work. End of the month rolls around they hit me with the R100 bucks odd bank cost (no problem), but before I can transfer money into the account to cover that - they raise a penalty of R310 because of going into overdaft - their reasoning is it is no the bank cost that put me into overdraft but the last payments by card that they cleared and approved BEFORE their bank cost rolled in.

R310 penalty to cover R100 odd, it is not like they giving me R100 - because in total I owe them R400+? It is not the size of the amount, it is how they created a money out of thin air. That is over 300% of what they now claim they covered for me. And please dont try and contact them, they can only send you a canned response.