Detailled event page not listed into assignment menu

Hello,
I have a display problem with JEM.
When somebody clicks on an event in the main table of my event list, the detail page stops to display the left menu left next to the table of events.
concretly here is my page :
www.dame-verte.fr/index.php/fr/agenda
If you click on one of the listed events to display the detail, the left menus named "cursus de formation" and "cercles chamaniques" disappear
I can't configure those left menu/modules to appear on JEM detailled event page because the detailled event page is not listed into the proposition of the assignment menu (So I can't choose it to make this menu appear on it)
I have already upgrade to JEM 2.2.1 but the problem is the same
I use joomla 3.8.3 stable version.
Do you have an idea, why I can do to solve this problem ?
Thanks a lot for your help !

Hi, the easiest solution for this is: choose for these modules on the left side: thar thay will be shown on all menues (except the one where you don't want them. Now you have chosen that they should be shown only on some chosen menues

Hi jojo,
I have tested your suggestion today on my left menu "cursus de formation" but this solution doesn't solve the problem. No change.
And the detailled event page is still not listed into the proposition of the assignment menu.
Any idea to solve it ?

It will not be listed that's right. Because of that you need "show on all pages except.."
In my case this worked always, sorry.

:blink: so ... no solution