You own 2 listings, the appartment has no available dates at all (it is also not in the search system), but the cottage has availalble dates, also in feb/march 2022. When i simulate a booking it seems to work well. Maybe the guest should provide you more information on the issue they encounter (error-message ?).
I have the same problem. I got my booking settings to unlimited but people can only book up to one year head. Also I can’t set my price more than one year ahead. Especially now people are already looking to book next year July and August but not possible. Big unconvience.