Zomato - Discount increased on outlet without agreement

* We are an outlet listed on Zomato in Jamshedpur Jharkhand Res ID ********. Recently the POC of Zomato had approached us to increase our existing discount from **% to **% for existing customer and give **% discount to new customer. We said that we will consider wether we would implement or not. On **th April **** at *:** pm we got a mail from Zomato that the discount has been updated. We reached out to POC he said that he had informed us about the discount. When we said that we have not given a confirmation for the discount he said it would benefit the store and he had taken a unilateral decision about our outlet. The margin in our business is very low and this has pushed it to negative.
* This has happened before also at that time we decided not to take action on Zomato and escalated it internally. However, the action is taken again.