AirBnB ****

I made a booking for the 27th and paid on the on the 27th for an AirBnB. After I paid and contacted the owner to ask further questions the host told me that I can’t come because they are fully booked and they had removed their stay off the calendar for the 27th of December. I tried cancel the booking but I can’t on my end cause I won’t get my full refund. I told the owner to cancel on their end and they said they can’t cause my booking is not showing on their end. I need help getting my full refund but airBnB with their terrible support is not helping me and I keep getting a run around from the app and the host, and nobody is speaking bout my refund at all, I need help ASAP