myrpg and ultra cosmetics

[15:21:51] [Server thread/ERROR]: Could not pass event PlayerInteractEvent to myRPG v3.0.45
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at org.bukkit.craftbukkit.v1_8_R3.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:228) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at net.minecraft.server.v1_8_R3.PlayerInteractManager.interact(PlayerInteractManager.java:463) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:759) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at net.minecraft.server.v1_8_R3.PacketPlayInBlockPlace.a(PacketPlayInBlockPlace.java:52) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at net.minecraft.server.v1_8_R3.PacketPlayInBlockPlace.a(PacketPlayInBlockPlace.java:1) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_73]
	at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_73]
	at net.minecraft.server.v1_8_R3.SystemUtils.a(SourceFile:44) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:715) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:374) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:654) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:557) [spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	at java.lang.Thread.run(Unknown Source) [?:1.8.0_73]
Caused by: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
	at java.lang.String.substring(Unknown Source) ~[?:1.8.0_73]
	at org.caliog.myRPG.Items.Armor.getInstance(Armor.java:75) ~[?:?]
	at org.caliog.myRPG.Items.Armor.isArmor(Armor.java:110) ~[?:?]
	at org.caliog.myRPG.Items.ItemUtils.checkForUse(ItemUtils.java:47) ~[?:?]
	at org.caliog.myRPG.Listeners.myListener.spellEvent(myListener.java:461) ~[?:?]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_73]
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_73]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_73]
	at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_73]
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.8.8.jar:git-Spigot-db6de12-3f3c65f]
	... 17 more