Hindustan uniliver pure it water purifier
No invoice privided

I purchased Pure It Water Purifier, a product of Hindustan Uniliver Ltd, on 06-03-08, I gave a cheque worth Rs.1800/-to the guy who brought the product, he said that he would provide me the invoice the next day, but after a week, I have no bill in my hand. Nor he provided me my ID.