@einarf is correct that LocMem cache is messy in production deployments, but actual issue that @zmrenwu experiences seems to be lack of permissions to see those forums.
Misago defaults to acting that content doesn't exist at all if user has no permission to see it. You should go to admin control panel, then "Permissions" and lastly "User Roles". Here three roles interest you:
- Guest (all not-signed in users)
- Members (all signed in users)
- Moderators (only selected users have this role)
You should see "Categories permissions" for each of those roles:
This will tell you what "Category role" users with this role have for each category on your forum. Here you can see "Moderator" role having moderator permissions in "News" and "Releases" categories: