Please check if you have Not XML rates added to your Booking.com property calendar on the left side where rates info is showing.
It should look similar to this image :
To change a rate plan to XML active, submit a request via your Booking.com account or call directly your Booking.com account manager and ask him to do it for you.
Important : reservations that came through not XML active rate plans will never come automatically in Hostify. You will have to manually create them in Hostify transferring guest info 1:1 from Booking.com.
Manually created Booking.com reservations won't auto-update its status if they get canceled on Booking.com platform.