HDFC Bank/Savings account — Closure of my account

I have taken salary account in HDFC when I was working. But I decided to go for higher studies later and they converted the account to Savings account. But since I am studying, I haven't been able to maintain a minimum balance of Rs. 5000/-. Foreseeing levy for not maintaining this minimum balance, I immediately sent mails to the support department asking for closure of the account. They have been unresponsive so far.