Zomato — fraudulent practices, stealing

I had an order of 219 rupees on zomato. The restaurant canceled after 2 hours. Meanwhile the restaurant provided me a promo of rs. 100 as compensation for delay. When i canceled the order they only refunded rs. 119, saying that promo has the other rs. 100. I haven't used the promo and when i asked them to cancel the promo they denied. It's clearly a fraudulent practice because we can use only one promo per order. If i get full refund then i can order a dish of rs219+ (Promo, usually rs. 75) but now i cannot avail the value of other promo. They haven't even delivered the order. I'm just asking my money back for a purchase i didn't receive and now my money is stuck