Amazon India — Wrong promotion code applied to my order

Address:	500002
Website:	Amazon.in

I have placed an Order#[protected] on 18 October 2016 for an amount Rs.10999/- by paying using my CITIBANK credit card 4617 xxxx xxxx 8999 through Amzon Mobile App installed on my COOLPAD NOTE 3 mobile phone. For that order actually Amazon & CITIBANK offered 15% cashback for orders placed through Mobile App and 10% cashback for orders placed on desktop.
They have credited only Rs.1100/- on 19-01-17 as Cashback to my CITIBANK account where as it should be Rs.1650/- as the order was placed using CITICARD on my mobile APP.
When I enquired about the wrong promotion applied, Amazon customer care representatives told that the remaining amount will be credited to my account within 2-3 days.
But today they are informing that no additional cashback will be given to me as I placed the order from desktop.
This is nothing other than cheating from these people.
Really the information that Amazon submitted "Order placed using browser" is absurd.
The faith about the Amazon will vanish in no time if it happens to several customers with the wrong data they are maintaining in their database.
I need corrective action from Amazon.