Would rather keep my money under my bed

I have a CHEQUE ACCOUNT WITH FIRST NATIONAL BANK, WORST DECISION TO EVER MAKE IN YOUR LIFE, every single month, I'm in the negative, for absolutely no reason, I call in to find out and they give me some sloppy excuse of oh when you want to the Shop then maybe you didn't have sufficient credit in your account for the transaction to go through and, well maybe it's just my thinking but wouldn't it say that it's declined? For the last 3 months, they have been taking amounts such as R700 for my account being over drawn, I don't have a over draft on my account, they never have a sufficient explanation for such but are always fast to take money as it comes in your account, they send me smses telling me that they have been calling me for my account being over drawn but I have never received one call? I find this company the biggest ******* around, what's the point of paying R104 bank fees for an account that you don't even feel safe having money go into because FNB always has some reason to take it?