Jicofo - Reservation : GET_SESSION_ID_ERROR

We use a self hosted JitsiMeet Server with authentication. It works fine.

We are trying to add reservation over REST API.

When all is goof, the reservation sytem sent en HTTP 200 message and it’s OK

The problem i s when the reservation system sent a message error to JICOFO (ie : wrong date or wrong mail_owner etc … : HTTP 409 or 4xx), JitsiMeet only displayed “GET_SESSION_ID_ERROR”.
The JSON message that sent by the Reservation system to JICOFO is not displayed (but we can confirm that JICOFO send the right message to the WebClient)

The problem seems to be on the JitsiMeet UI connexion screen

Any idea to solve this problem ?