Rufund for my booking from Booking.cm and pavallion

Hi i'm Lucky D Luthuli I made a booking with Booking.com on the 29 of February 2024 for stay at Pavallion hotel and I entered wrong date by mistake for my date booking and I paid for my booking now I tried calling them more than 3 times now sending them my email they promised me to return my calls coz the problem they asked for the pin they sent me after my booking but there is no pin only the confirmation number for my booking, the pin they are asking for it not there on my email so I want my refund or to choose another date but they are ignoring me please help. My confirmation number for my booking is ***