Mahaveer Electronics - Different item supplied

I sent my attender to buy an adapter of LG company. He said that's not there in stock then he encouraged my person to buy Sony brand. He agreed to replace if not required. As I use most of the LG branded items. I don't want to use it. And that doesn't matches with my adapter.
When I sent the person to buy something else by returning it. He refused to take it. And when he told that we will complain about it. He said that "there are many complaints are already registered on me. I don't mind to get one more. I know very well to handle government officials. I am paying bribe every week. Nobody will take any action on me. Do whatever you can."