Money debited from my bank account but transaction was not successful.

[santoshpur]

I tried to purchase an item for Rs. 1689.00 on 27th April 2014 through Net Banking from HDFC Bank. Amount debited from my Account but transaction was not sucessful. Since today I have not received the money back. After several attempt, fortunately I was able to contact the help line and concern persons listen all the matter and tel me that  72 hours nees to enquire about this. But all are vain.