HDFC Bank — Negative balance

Hi, i have salary account in hdfc 2 years back when i was working at that time. After that i change company Recently . and i use my hdfc bank but they cut my 1200 rs without any reason ..i earned very hardly and they cut without any reason and show 300 in negative balance.
Even they are not intimated verbally... According to rbi guidlines on salery account banks not charge even its negative balance.
I approach branch, but they behaved rudly & refuse to close account.
Plz juistice to me.I earned very hard .and salery is also not high . What is the solution?
What is the action will take against this bank.