[19:28:09] [Server thread/ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'ognci' in plugin OGNangCapitem v1.0
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[patched_1.12.2.jar:git-Paper-1592]
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:151) ~[patched_1.12.2.jar:git-Paper-1592]
	at org.bukkit.craftbukkit.v1_12_R1.CraftServer.dispatchCommand(CraftServer.java:685) ~[patched_1.12.2.jar:git-Paper-1592]
	at net.minecraft.server.v1_12_R1.PlayerConnection.handleCommand(PlayerConnection.java:1478) ~[patched_1.12.2.jar:git-Paper-1592]
	at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1283) ~[patched_1.12.2.jar:git-Paper-1592]
	at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:45) ~[patched_1.12.2.jar:git-Paper-1592]
	at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:5) ~[patched_1.12.2.jar:git-Paper-1592]
	at net.minecraft.server.v1_12_R1.PlayerConnectionUtils.lambda$ensureMainThread$0(PlayerConnectionUtils.java:14) ~[patched_1.12.2.jar:git-Paper-1592]
	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~[?:1.8.0_191]
	at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_191]
	at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) ~[patched_1.12.2.jar:git-Paper-1592]
	at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:850) ~[patched_1.12.2.jar:git-Paper-1592]
	at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:423) ~[patched_1.12.2.jar:git-Paper-1592]
	at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:774) ~[patched_1.12.2.jar:git-Paper-1592]
	at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:666) ~[patched_1.12.2.jar:git-Paper-1592]
	at java.lang.Thread.run(Unknown Source) [?:1.8.0_191]
Caused by: java.lang.NoClassDefFoundError: eterlib/f/FItem
	at eternalrvn.ognangcapitem.UI.open(UI.java:30) ~[?:?]
	at eternalrvn.ognangcapitem.Main.onCommand(Main.java:66) ~[?:?]
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[patched_1.12.2.jar:git-Paper-1592]
	... 15 more
Caused by: java.lang.ClassNotFoundException: eterlib.f.FItem
	at java.net.URLClassLoader.findClass(Unknown Source) ~[?:1.8.0_191]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:156) ~[patched_1.12.2.jar:git-Paper-1592]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:104) ~[patched_1.12.2.jar:git-Paper-1592]
	at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_191]
	at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_191]
	at eternalrvn.ognangcapitem.UI.open(UI.java:30) ~[?:?]
	at eternalrvn.ognangcapitem.Main.onCommand(Main.java:66) ~[?:?]
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[patched_1.12.2.jar:git-Paper-1592]
	... 15 more