Bangalore Metropolitan Transport Corporation [BMTC] — not returning my change amount / bus conductor behavior

Address:

560068

I was going from central silk board to sap lab (Bus stop) by bmtc bus. Bus no. Ka-57f-3415. I buy ticket with bus conductor that was of 23 rupees. I gave him 100 rupees note and he return 70 but he should return 77 rupees. I asked him to give my 7 rupees change but he told i will give at sap stop and he refused to give me 7 rupees. He had change but don't want to give and said i will not give you, i have not change and start talking rudely. 200 passenger used bus, it is impossible that no one give him any coin. After requesting multiple time he gave me change on another stop that was after and far from my bus stop