DMart — Never give change to customer

Address: Bangalore, Karnataka

I have purchased a product on may 31, 2015 and bill amount was 1010. I gave them 1100 but they refused to give 90 rupees change instead of that they order(not requested) me to purchase a product worth 90 rupees. When I don't accept that they started shouting at me. Those are doing a business with a change also. Even though they have a change with them. I complaint the manager also but they are least bother about it. They do this for every customer. They behave very rudely. Please take necessary action