I think many of us had the experience PBF
There is a topic where you can vote to help members who list on many websites to manage their calendar.
Normally if there are plenty of votes, HE may put into production.
I concluded an exchange and in checking on the other website, the calendar was still opened with the instant booking turned on. So what about my stay if it was rented.
After 3 reminders to the host, the dates were closed in the rental calendar.
Moreover, some people reply there is no avaibility but it is not the true reason.
It is simply that your request does not suit them for one reason or another (lenght of the stay, the prefer reciprocical exchange, they are in discussion with another member…).