Update the ID document and personal details of one guest on a stay, for example after collecting a passport for local guest registration. guest_id is guests[].id from Query Reservations.

The change is saved to the guest's profile in Hostex, not only to this stay: if the same guest is linked to other stays, they show the new values too. Fields you leave out are unchanged. Values cannot be cleared through this endpoint; null or an empty string is rejected. id_number must be sent together with id_type. Changing name also stops later channel syncs from overwriting the guest's name, the same as editing the name in the Hostex web app. Other fields synced from channels only fill in empty values, so they do not overwrite what you write here.

Returns 404 when the stay does not exist, or when the guest is not linked to this stay or belongs to another account.