phải show lỗi trong console thì mới biết mà lần chứ
[19:10:08] [Server thread/INFO]: HM_BossVN issued server command: /mi
[19:10:08] [Server thread/ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'mi' in plugin MyItems vMysthoria
at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[spigot.jar:git-Spigot-4af49dc-c5e9a16]
at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:141) ~[spigot.jar:git-Spigot-4af49dc-c5e9a16]
at org.bukkit.craftbukkit.v1_9_R2.CraftServer.dispatchCommand(CraftServer.java:645) ~[spigot.jar:git-Spigot-4af49dc-c5e9a16]
at net.minecraft.server.v1_9_R2.PlayerConnection.handleCommand(PlayerConnection.java:1349) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at net.minecraft.server.v1_9_R2.PlayerConnection.a(PlayerConnection.java:1184) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at net.minecraft.server.v1_9_R2.PacketPlayInChat.a(PacketPlayInChat.java:45) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at net.minecraft.server.v1_9_R2.PacketPlayInChat.a(PacketPlayInChat.java:1) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at net.minecraft.server.v1_9_R2.PlayerConnectionUtils$1.run(SourceFile:13) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_171]
at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_171]
at net.minecraft.server.v1_9_R2.SystemUtils.a(SourceFile:45) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at net.minecraft.server.v1_9_R2.MinecraftServer.D(MinecraftServer.java:726) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at net.minecraft.server.v1_9_R2.DedicatedServer.D(DedicatedServer.java

99) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at net.minecraft.server.v1_9_R2.MinecraftServer.C(MinecraftServer.java:665) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at net.minecraft.server.v1_9_R2.MinecraftServer.run(MinecraftServer.java:564) [spigot.jar:git-Spigot-4af49dc-c5e9a16]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_171]
Caused by: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
at java.util.ArrayList.rangeCheck(Unknown Source) ~[?:1.8.0_171]
at java.util.ArrayList.get(Unknown Source) ~[?:1.8.0_171]
at be.maximvdw.placeholderapi.PlaceholderAPI.replacePlaceholders(PlaceholderAPI.java:101) ~[?

]
at api.praya.agarthalib.builder.support.SupportMVdWPlaceholderAPI.setPlaceholders(SupportMVdWPlaceholderAPI.java:19) ~[?

]
at core.praya.agarthalib.utility.TextUtil.hookPlaceholderAPI(TextUtil.java:128) ~[?

]
at core.praya.agarthalib.utility.SenderUtil.sendMessage(SenderUtil.java

4) ~[?

]
at core.praya.agarthalib.utility.SenderUtil.sendMessage(SenderUtil.java:25) ~[?

]
at com.praya.myitems.c.m.a(CommandMyItems.java:1290) ~[?

]
at com.praya.myitems.c.m.onCommand(CommandMyItems.java:1117) ~[?

]
at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[spigot.jar:git-Spigot-4af49dc-c5e9a16]
... 15 more
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