Hello @Fanny166,
You'll have to contact Airbnb support to discuss the issue and make sure that they have allowed channel manager access on your Airbnb account.
I don't use a channel manager so don't know how they work with Airbnb.
Type "contact airbnb" in the "Search the community" box on these forum pages where you posted your question. Scroll down a little in the list of suggestions that appears and click on the "Contact Airbnb: A Community Help Guide[UPDATED]" one. That lists phone numbers and ways to contact them via Twitter or Facebook.
You may also have to contact the support organisation for your channel manager.
Steve.