Indian Overseas Bank — amount deducted unnecessarily

Money (177rs) is being deducted from my account unnecessarily, infact I haven't taken money from the atm nor swiped it anywhere nor did an online shopping or payment, why do they deduct it without any proper message for what it is being taken, what explanation does the IOB have for this? Pathetic ! If there is any genuine reason to why it is taken, they should be a proper message given to the card holder.