THE UNDERGROUND PORTAL NOT WORKING

[Arcstone]

Plugin version:The Underground 5.7

Issue: I downloaded the ewg version 6.34 and the underground version 5.7, I am using spigot 1.10I and it said tht they are compatible with spigot 1.10. Everything works fine. but the only thing is tht the portal is not working. When ever i lit the portal , a block breaking sound comes and nothing happens, in the console it says "unable to pass PlayerInteractEvent to the plugin TheUnderground" and somewat down the console it says "Your bukkit version is not compatible with the library"

Link to settings.json: http://pastebin.com/c5eZ4BXb