run through the setup procedure , but kept the redis database.
The problem remained.
deleted the redis database files
run nodebb setup
That way I got a clean install without data and with default settings.
The problem still exists:
When you define a new reward the forms and pull downs are populated.
After saving the rewards, leaving the page and coming back, the pull down menus for existing rewards are not populated and empty, while creating a new reward works well.
After saving and reloading the rewards page, the error 'illegal reward. no inuts found' is displayed.
Last but not least, no rewards are awarded to users.
Is there a reason that you are using Plesk? Tools like that generally make support and management vastly more difficult. Something like a NodeBB install is so easy, but Plesk can make it so hard for no reason.