OYO Rooms - Cheated by OYO rooms

We booked OYO rooms “OYO**** Hotel Rock Heaven” at Naldhera road in Shimla from **th June to **th June ****. We are a family of * (* adults and * kids aged ** years and ** years). When I tried booking the hotel through OYO website or OYO mobile app, it was showing a limitation of booking only * persons per room. Hence I called up OYO customer care number. I explained the problem to the lady from OYO customer care about this and she said that she can book the room for me. I explained to her again that we need a single room for * of us. Based on this she confirmed my booking over the phone and I made the advance payment over the net link sent by OYO.
When we reached Hotel Rock Heaven on **th June, the reception staff stated that the booking is not for * of us and we have to pay INR **** extra for the kids. I called the OYO customer service number and spoke to them again. They said that as per OYO policy that any kid above * years is chargeable. But this was not informed to me when I booked my room by the OYO customer service lady. The OYO customer service person told me that they will raise an escalation and audit team will review the case and refund if my compliant if found valid. I even told them to hear my audio conversation when I booked the room when the lady booked my room for * persons.
After that, I made a lot of calls to OYO number asking for the status and I was not getting a proper answer. They are not ready to share the telephonic conversation with OYO when I booked my room also. I already sent my extra payment receipt to them as well but no luck. Request your help to get the INR **** refund from OYO rooms. Thanks. My payment receipt is uploaded on your site. I stay outside India and would prefer our interaction through emails.