how to repair error?
If a player opens a box on the road or RT and doesn't take everything out of the box, other players can't open that box.

I checked it for you, and everything works fine for me. Check the same thing without the plugin, without all plugins, only with this plugin.

yes also it made me, you have to allow lootentity, but be careful then players can grow your furnaces and quarries :-(

The work of the plugin is based on the id of the owner of an item.
Accordingly, items spawned by the game do not have an owner (number zero).
So some other plugin assigns the owner of the box when it is first opened.
Test the plugin alone without other plugins. And also look for the problematic plugin one by one.