If your an travel affiliate with any major network, be warned that a small percent of hotels are starting to disable their available inventory through a system call Pegasus "hotel booking back-end used for all hotels"
What does this mean:
Hotel are still showing on your White Label or non white label sites, and the links are available from any links to from your websites", BUT if a customer attempts to make a booking they will be warned that the hotel doesn't have any rooms available.
But if the user calls the hotel directly or visit the hotels own website they will be able to make a booking. "without you earning a commission"
1. You could be promoting a hotel that you can't earn commission own.
2. Hotels don't want to remove their site completely because people would not be able to find them, so basically they are using your sites as free advertising to direct people to them, who after attempt a failed online booking calls them directly and make a booking.
Use Hotel Search where only hotels with available rooms are shown, and force users to enter a date "instead of browsing Hotels, then entering dates"
Identify hotel that are claiming no rooms available, call and verify. If the online status and offline status disagrees, remove that hotel from your system, and send a email to your affiliate manager.
I just found this out the hard way. after about a month of paid and non paid promotions.