Dupers are not working on a Paper server

To enable dupers on a paperspigot server, simply follow these steps:

1. Stop the server you wish to enable dupers on.

2. Head over to the "Properties" tab.

3. Click on the "Presets" button.

4. Under the "Enable World Dupers", click on "Enable".

5. Done! Start your server and the dupers should now be enabled.