Please read How To Deal With A Failed ATM Transaction In India before reading this page. Before filing complaint with a Banking Ombudsman (BO), one needs to make a written complaint with the concerned bank (Issuing Bank - The bank that issued your ATM/Debit Card) and wait for a response. If the bank claims the transaction to be successful or does not respond to your complaint even after 30 days of the date of submitting your complaint, you can make a complaint to the Banking Ombudsman. Important information regarding complaint before the concerned bank(s) - Issuing Bank and Acquiring Bank - are given in this page. Please go through the same. Complaints to BO can be filed in several ways such as Online, Email, By post or Hand Delivery, etc. You need to file the complaint before the particular BO under whose jurisdiction the Issuing Bank branch is located. For example, if your ATM card is issued by SBI, New Delhi branch, you should file your complaint to the BO, New Delhi.