Indian Overseas Bank — money issue

Address:

643001

My name is ashwanth i am holding an account in your bank in ooty branch.
(Indian overseas bank).

Account name is : ashwanth johnson
Account number : 33135
Branch :ooty
Ifsc code : ioba0000786

I have withdraw rs 5000/ on 8/05/18 at 12.30 pm. I entered rs 5000 in indian overseas bank atm. But i have received only 2000. I havent received 3000, but it got got debited from my account. I have filed the complaint in the bank immidetely, they are not taking proper action.
Its going to be one month there is no response from them. They are telling me to contact the atm head office, where i dont have the address or phone number. Please do the needffull. I want my money back. I almost visited the more than 10 times. Though its not my mistake, they are making me to come again and again.