[Voxel sniper not working]

Hi so i think i got the right thing. https://pastebin.com/SZiHj6uf is the pastebin link. i dont know if this is the right thing but hopefully it is

[Voxel sniper not working]

Hey i tried to install voxelsniper onto my server but the /u command doesn't work. not entirely sure how to make it work as i tried most things, if anyone else has experienced this and fixed it could i please know how?