Zomato — not giving full cashback inspire being new customer

Hi
I had ordered two biryani worth of 448 from zamato. I was eligible for new50 promocode but due to some reasons customer care guy said you please order your food and we will compensate for that. But later on i got only 100 z credit only inspite of 250z credit as per the customer care guy. And later on they are saying we can only give you 100 z credit. I need a responsible answer from you guys and need compensation for the loss.
Order i'd :[protected]
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