Problem when I want add participant to my agenda


I have create a new user.
When I want add him to an activity I can’t found Him.
But when I want share a folder, it’s works.

I don’t understand because I have no problem with other users
Do you know why I have this problem?

Kind regards,


Do you use the native user management in Nextcloud or external backends? Did the user already login? Did you logout and login again? You are using NC 12.0.5?