@TomasandAlenka0
Hi Tomas, yes I agree this is very unfair but there are some ways to prevent this from happening in the future.
If a guest wants to cancel even as soon as they check in (it is very rare but happens), I let them and I open my calendar up and usually I get it booked at a lower price. At the end of the day, you don't want someone who really does not want to stay in your place to stay because they will be resentful and it will lead to this or maybe worse such as them reporting false issues with your home which will lead to issues with airbnb. I know that providing them a full refund is not fair but the system is not fair and so you have to manage that.
I recently had a guest for a $2000 booking request to cancel at 9pm on the day of check in. She was not happy with the place. I let her go penalty free and she did not leave a review. I was very nice about it. I ended up re booking the place at $1700. So I lost $300 but I saved myself from a 1 star rating. It was worth it. Not only that, by I saved myself aggravation and her complaining to airbnb which does not help our status.
The general rule of thumb is about 2-5% of guests are problematic as in any business I operate in, I find 2-5% of customers are problematic. As such, I usually factor this in when I operate my business and I would rather let those 2-5% of guests out of our deal drama free then deal with the issues they come with. At the end of the day, you can always open your calendar up at a lower price and get it booked. Yes you may lose a few hundred dollars but you have to ask yourself, it is worth receiving a 1 star review for the difference which may be a few hundred dollars?
Another way you can go about this is ask the guest to kindly ask Airbnb to remove the review. If you also left this guest a bad review, you can suggest in a subtle way that you would request your review of them to be removed as well.