Amazon India - false promise to force for placing order

Recently I ordered a OnePlus ** phone from Amazon(Order #***-*******-*******) and it didn't deliver even after * days when it was on same day delivery...on the *th day, when Amazon didn't deliver and cancelled my order from their side I reached customer support. In those * days I struggled a lot to get my delivery and was reaching customer support multiple times., I was waiting as it was an exchange order and day after day * days went by like anything. Reached customer support multiple times, to support their delivery taken * days leave from office as it is important that I should stay at home to hand over the old mobile exchange. But after * days when it got cancelled, now the price increases and exchange bonus dropped off on the same phone. Reached the Amazon agent and he promised over call that they will refund **K as refund and sent a written confirmation via email mentioning that they will refund me the amount Rs **,*** paid after the new order if I am purchasing the same item...as he promised and sent an email confirmation, I re-ordered the same item with same method(Order #***-*******-*******) as he promised and gave written confirmation. Until the order was placed