@Trine12 It isn't acceptable to try to charge a guest more after their booking is confirmed, whether they have already arrived, or not, because you didn't have your settings correct. It's unfortunate that you didn't know how to add the cleaning fee, but you'll have to take a hit on this booking, and chalk it up to a learning experience. Trying to charge a guest more after the fact will very likely antagonize them and lead to a bad review. Hopefully these guests leave the place in decent shape, not requiring above and beyond cleaning.