I'm aware that this was asked in the past but no apparent solution was provided and I didn't want to reopen an old thread.
We have a couple of users that are Managers in a course, they can hide sections but can't unhide them afterwards. If they go directly to the section URL they got a permission denied message. They have also lost the ability to switch roles inside that course. It looks like this is happening to all Managers of that single course, but System Managers work fine.
This used to work in the past and suddenly stopped.
We are running moodle 3.6.2