[22:17:32 ERROR]: Could not pass event PlayerCommandPreprocessEvent to GUIShop v7.0B
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at net.minecraft.server.v1_8_R3.PlayerConnection.handleCommand(PlayerConnection.java:1154) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:997) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:45) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:1) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) [?:?]
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) [?:?]
	at net.minecraft.server.v1_8_R3.SystemUtils.a(SourceFile:44) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:715) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:374) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:654) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:557) [spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at java.base/java.lang.Thread.run(Thread.java:834) [?:?]
Caused by: java.lang.IllegalArgumentException: No enum constant org.bukkit.Material.WHEAT_SEEDS
	at java.base/java.lang.Enum.valueOf(Enum.java:240) ~[?:?]
	at org.bukkit.Material.valueOf(Material.java:1) ~[spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	at com.pablo67340.guishop.listenable.Menu.preLoad(Menu.java:98) ~[?:?]
	at com.pablo67340.guishop.listenable.Menu.<init>(Menu.java:57) ~[?:?]
	at com.pablo67340.guishop.listenable.PlayerListener.openShop(PlayerListener.java:30) ~[?:?]
	at com.pablo67340.guishop.listenable.PlayerListener.onCommand(PlayerListener.java:115) ~[?:?]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:?]
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]
	at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[?:?]
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.8.8.jar:git-Spigot-21fe707-e1ebe52]
	... 16 more