I too have had the same problem. Booked a stay (have already stayed there) but it isn't in my airbnb account and I couldn't leave a review. In order to contact and communicate with the host I had to make a tentative booking at the same place for a different time and then use the "contact host" to commmunicate. AirBNB Support could not help me, and cannot find a booking/account under any of my email addresses. How does this happen?? I was charged through AirBNB so there must be a record somewhere!