Magicpin — Voucher redemption

I bought 8 vouchers of Dakkhan hotel Narhe Pune worth rs 2000 each from Magicpin App. When I visit hotel they refused to accept multiple coupons at same time. However it is not mentioned in their terms and conditions. They redeem only 1 coupon. When I raise complaint against the merchant magicpin customer care is unable to resolve my issue. I paid bill worth Rs 18195 however as per coupon amount should be 12554. Because of this pathetic service my loss is around 6k and they are just offering me 350 coupons. Plz resolve my issue