Recently I bought some items from Total Mall, Old Airport Road and accidentally lost the bill. Later I realized that I had picked the wrong product in hurry. I went back after 5 days and the manager and the staff were very helpful.
They again generated the duplicate bill and helped me exchange the product with the one I wanted. Even though they were very much occupied (and it was my mistake of loosing the bill), they were very helpful. Really appreciate their humble support. (However the Basement parking is terrible - I was charged Rs. 200 for lost parking slip. I received a manually signed unauthentic slip for it. A bad way to make money. )