[Resolved]  HDFC Bank — my salary account goes negative balance

Address:

Kolkata, West Bengal, 700070

Dear team, i have salary account in hdfc 4 years back when i was working at that time. After that i changed company & they provided other bank account. Recently i got a sms from hdfc bank to deduction of non maintenance charges. So immediately i checked my bank account its showing -4k balance. But in bank statement, there is no such negative balance mentioned. Then i came to knew that, the bank converts my salary account into savings account & charged every month.. Now its around -4000 negative balance. Without my permission how can the bank charged non maintenance balance from corporate salary account (Zero balance)? Even they are not intimated verbally... I had sent a query to hdfc support team ([protected]@hdfcbank.com) regarding my salary account on 27th july [protected]@1.2pm. But no one get back to me. I left my job on 31st june 2017. And i received a mail from hdfc bank on 12th jan, 2018 regarding features and offers of salary account and also written there that they will converted my salary account to saving account and also mentioned there saving account charges details below... But in that mail, no were mentioned that they will charged from me panelty for non maintaing that account. I will show you that mail and other evidence, if require.
According to rbi guidlines on savings accounts, bank cannot charge any panelty for even its negative balance.
There is no option for closing account online.
4000 is huge amount to me. And i am not going to paid this. What is the solution?
What is the action will take against this bank.
Bank account number - [protected]