Non payment for services

We are a small food service operation in a tie up with zomato for providing online orders to customers. The following order, (39404581) was delivered to a customer who had made the payment to zomato for the services provided by our restaurant. The same was not paid out to us stating that the order was delayed and the money was refunded to the customer. Now we have already provided the food and service to the customer for which we are to be paid, but we are being denied payment on unethical grounds. On constant follow-up, they have now stopped responding to our queries about the same