diff --git a/CHANGELOG.md b/CHANGELOG.md
index 462306904..521788fc8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@ and this project adheres to
 
 <!-- write down unreleased development here -->
 * [person] accompanying course: close modal when edit participation (https://gitlab.com/champs-libres/departement-de-la-vendee/chill/-/issues/420)
+* [person] accompanying course: treat validation error when editing on-the-fly entities (https://gitlab.com/champs-libres/departement-de-la-vendee/chill/-/issues/420)
 * [search]: listing of parcours display changed (https://gitlab.com/champs-libres/departement-de-la-vendee/chill/-/issues/410)
 * [user]: page with accompanying periods to which is user is referent (https://gitlab.com/champs-libres/departement-de-la-vendee/chill/-/issues/408)