Airbnb Reservation Pricing Issue - Host Demands Extra Payment After Booking

I searched for a place to stay and found one at a reasonable price. I made the reservation, but then the host claimed that Airbnb had reduced the prices and demanded more money than initially agreed upon. The host said that if I didn't agree, I should cancel the reservation. I refused to pay the extra amount and canceled the booking. Now, looking at my emails, I see that there is no refund. I'm being charged for a place I never stayed in. What kind of scheme is this? Please rectify my issue!