HDFC Bank — Balance is being cut from the account

Previous day I was not use to keep Bal in my account but they used to charge for this 600 rs every month saying that not maintained the bal etc. Then I started doing transactions plus I used to keep Bal in my account but then still they cut the money but this time 5000 . Seriously. It's a huge amount for a middle class person. I need to know what charges is this which u people take or I need my money back . I want an answer.