Cafe Coffee Day — Refused exchange my product and rude customer service

I went to the cafe coffee day store near visat gandhinagar highway in chandkheda and purchased a light roast 200gm coffee powder. I wanted to buy a medium roast but bought the light roast by mistake. I went there after 45 minutes with the bill to exchange for a medium roast and the server refused to make an exchange. I insisted to speak with the manager and the manager name was kishanth or kishore. He was unbelievably rude with me over the phone, refused to listen to me and said " if you want a medium roast just buy one and we wont take exchange. " I was very disappointed by their customer service, I have coffee day customer for many years and now I will never go back there. Worst customer service every.