@Lydia161
I have exactly the same problem.
It is indeed the case that the listing calender shows available check-in dates, and I think think this is really confusing as a guest - it's the availability calendar, not the check-in calendar. As a guest, if I want to book two nights, but one of the nights is shown as not available, I am thinking that this listing is not for me, because it's only available on the first night...
On the other hand: when the guest has preselected the dates for their stay of two nights, your listing will appear.