Item sold is duplicate and do not provide sell slips to avoid sale tax

I bought a tat sky remote from the shop hari palace electronics,I asked for the sell slip bu the shopkeeper denied to give me that, after came back to home I turned it on and it DID not work , I go back to the shop and asked to replace that, the shop owner denied that there is no policy of change and his coworker threat me with abusive language. That tata sky remote is actually a duplicate and not original.