Union Bank Of India — ink stained note from atm

Address: Thane, Maharashtra, 400601

2 august 2017
Union bank of india, 3petrol pump branch, thane west:
Ink stained rs.2, 000 note from their atm & the very arrogant and rude cashier.
I am a customer o[censored]bi for the last eleven and half years.
On 30th july 2017 i withdrew rs. 9, 000 from ubi’s atm placed at their 3 petrol pump branch, thane west.
There was an ink stained two thousand rupee note, which i noticed yesterday only when my fruit vendor politely refused to accept showing the rubber stamp ink stains on it. I had to cancel my programme of buying even essential commodities as i did not have much money left. (Inconvenience caused by ubi)
Today i went to their branch and showed the ink stained note to the cashier. He asked me to produce the advice slip that one normally gets from most of the atms. I told him that i was going green and did not opt for the slip. Instead i showed him the pass book entry. He insisted on producing the slip as it would only prove what i was saying. I told him that whatever info that would be there in the slip would be there in the pass book as well. But he would not agree and insisted on the slip. (Now from where am i to produce the slip which i have not obtained on that day?) so i asked him finally whether he was going to exchange it for me or not as the discussion was prolonging (His time was paid for by the bank, but not mine; my time was being wasted) and reaching nowhere. To this he said no and gave me an unsolicited advice to deposit into my a/c. The cashier short of called me a liar. I should think that the cashier was trying to cover up something and wanted to send me back some how. Is it not possible that this note must have been given to the cashier by his wife or daughter to exchange it in the bank and the cashier must have stealthily put it into the atm!
I was taken aback by the rude and arrogant attitude of the cashier.
I approached the dy. Br. Manager who instantly helped me out with it. He said that he did not have enough money on him to exchange and so asked me if he could deposit that amount into my a/c. He was a hindi speaking north indian, polite to the core. I understood his embarrassment & helplessness and so agreed. He went out and deposited the note into the cdm himself and handed me he advice slip.
I thanked him enough and asked him what difference it made if i produced the slip (Thinking that i will not go green anymore and get slips). To this he gave a very sweet broad smile. I suggested to the manager to educate their staff to talk wisely and not otherwise.
I would like to know how to protect my interests in such events in future.