@German281 My advice, I always ask the guest to cancel the reservation and to reach out Airbnb Support for
a refund. Basically, once they cancel, they have to get with Airbnb support, Airbnb will contact you to let you know the guest is seeking a refund, you can deny or accept or mediate a price. At the end, Airbnb will know if the guest is been unreasonable and they can banned them or put a red flag if they come up with the same drama again in the future. Do not refund while they are staying, and tell them, to go ahead cancel and contact Airbnb and that Airbnb will assist them in finding a new place.
Any issue I find or I get notified about the home that I think will cause an issue with guest, I let the guest know before they check in so they have the chance to cancel and book another place.
Some guest need to understand that renting Airbnb you are expected to have some home related issues, like ant season and getting ants in the home, etc. If they do not want to have any issues like that they need to book a hotel.
Always made aware of your up coming guest about the home situation and if they are ok with it.
Ask your cleaning crew to send you pictures once they are done, this will prevent guest from making false accusations to get their money back, and always take cleanings issues serious that is your bread and butter of your STR.