OYO Hotel Telehaus International - Oyo denied checkin no refund

I have booked * rooms in oyo ***** Hotel in banglore for my family stay. As my stay was sure, i paid in advance to confirm it. But due to heavy demand on that day the hotel denied me check-in right at **:**pm even after waiting for *hrs in reception with family and luggage giving reason of overbooking by oyo. They demanded me **** extra per room if i wanted it or else i should contact oyo and get shifted to other hotel. I tried to call oyo but in vain. I immediately had to book another nearby hotel urgently at ****/room upfront as i was getting late. It was clear that my rooms were sold at higher price by hotel manager. Oyo is not approving refund as hotel have mentioned no check-in. I have called oyo more than ** times since then but no positive response. Sometimes they are even disconnecting calls. Feeling cheated and harrased.