Errror

[04:30:03] [Server thread/INFO]: [ShopGUIPlus] Enabling ShopGUIPlus v1.0.6
[04:30:03] [Server thread/ERROR]: Error occurred while enabling ShopGUIPlus v1.0.6 (Is it up to date?)
java.lang.NullPointerException
	at org.bukkit.inventory.ItemStack.<init>(ItemStack.java:94) ~[spigotRSNAPSHOT.jar:git-Spigot-1649]
	at net.brcdev.shopgui.utils.Utils.loadItemStackFromConfig(Utils.java:85) ~[?:?]
	at net.brcdev.shopgui.managers.ShopManager.loadShops(ShopManager.java:67) ~[?:?]
	at net.brcdev.shopgui.ShopGuiPlugin.init(ShopGuiPlugin.java:63) ~[?:?]
	at net.brcdev.shopgui.ShopGuiPlugin.onEnable(ShopGuiPlugin.java:45) ~[?:?]