Good morning dear Marc and thank you for your question!
The messaging system inside the detail of your reservations can be activated with the portals Booking.com5 and Airbnb. With reference to Booking.com5, make sure that the messages have been activated since teh beginning of your connection with our channel manager.
For Airbnb, make sure that the portal sends to you the alias e-mail adresses of your guests.
If you cannot see the messages of your guests from the portals, send us a message so that we can check your specific situation.
I wish you a great day!