Upvote:2
To answer the question "is this fair?", I say, yes.
You booked a last-minute, non-refundable room. Effectively, robbing the hotel from an opportunity to sell the room to someone else.
If you make mistakes, customer care of Booking.com tries to plead your case with the hotel, and often hotels are willing to waive the cancellation fee (I've made mistakes, and customer care of Booking.com has always been able to get the cancellation fee waived for me). But due to COVID, hotels are going through a rough time. They may be far less lenient than they were in the past.
Having said that, look closely how the prices is broken down. You should not have to pay any city tax (that is, European style city tax, also called tourist tax (US city tax is more like VAT in Europe)). If there are any cleaning or similar fees included in the price, you have a strong case you don't have to pay those.