KamikazePokemon

Hello, I've been having some issues with the item called "Infernal Armour". People have been using it to destroy the spawn area, factions etc. I've allready banned the item but people still have it somehow. Can someone please tell me how to stop the usage of the "Infernal Armour"? I have now got a plugin, it prevents the usage of the Infernal Armour but it crashes my server every 20 minutes, can someone please help me fixing this? Regards, KamikazePokemon.