As the name says, I host a server to play with my friend and we wanted to spawn some items to mess around with zombies, but none of the "add 1, 5, etc" buttons do anything when pressed, even when alone on the server. I have admin perms and don't seem to have issues with anything else from the admin panel.
I've tried looking up similar issues but the only ones I find are people getting errors where as I don't even get any errors. Simply nothing happens or is added to my inventory.