[03:21:15 ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'upitem' in plugin UpgradeItems v1.0
at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[patched_1.12.2.jar:git-Paper-1618]
at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:152) ~[patched_1.12.2.jar:git-Paper-1618]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.dispatchCommand(CraftServer.java:685) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.PlayerConnection.handleCommand(PlayerConnection.java:1492) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1297) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:45) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:5) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.PlayerConnectionUtils.lambda$ensureMainThread$0(PlayerConnectionUtils.java:14) ~[patched_1.12.2.jar:git-Paper-1618]
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~[?:1.8.0_221]
at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_221]
at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:850) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:423) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:774) ~[patched_1.12.2.jar:git-Paper-1618]
at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:666) ~[patched_1.12.2.jar:git-Paper-1618]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_221]
Caused by: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
at java.lang.String.substring(Unknown Source) ~[?:1.8.0_221]
at me.orineko.upgradeitems.manager.storage.StorageMethod.setNameLevelItem(StorageMethod.java:51) ~[?

]
at me.orineko.upgradeitems.manager.storage.StorageMethod.upgradeLevelItem(StorageMethod.java:81) ~[?

]
at me.orineko.upgradeitems.commands.CommandMain.onCommand(CommandMain.java:86) ~[?

]
at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[patched_1.12.2.jar:git-Paper-1618]
... 15 more
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