Recently I read an article about how banks are playing around with how they post debits to your account in order to purposely cause overdrafts. I have personally experience creative banking with a national bank so I am familiar with the complaint route. If your bank really is doing something wrong they become very responsive when they know you are filing a complaint with one of the below agencies. Good luck!
If your bank is a local bank then you can contact the Dept. of Banking and Insurance.
NJ Department of Banking and Insurance - Home
If your bank is a National Bank, like BOA then you need to contact the Comptroller of the Currency Administrator of National Banks.
OCC: Consumer Complaints and Assistance
You may also find some answers to your questions here.
Federal Reserve Consumer Help