No user shown in user backend

Hello everybody

I installed a few months ago a nextcloud v. 14 on a shared hosting, so i am kinda new into it. After i updated it to 15.0.5 i can’t access the user configuration under /index.php/settings/users. On the left side all groups and number of users are shown correct, but on the right side where the table with usernames, storage etc. should be its only written “no users”. It’s also not possible to creat a new user account.

everything else works as it should. do you have any idea how to solve this issue?

best regards