at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:140) ~[craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at org.bukkit.craftbukkit.v1_12_R1.CraftServer.dispatchCommand(CraftServer.java:623) ~[craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at net.minecraft.server.v1_12_R1.PlayerConnection.handleCommand(PlayerConnection.java:1326) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1186) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(SourceFile:37) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(SourceFile:9) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at net.minecraft.server.v1_12_R1.PlayerConnectionUtils$1.run(SourceFile:13) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_131]
    at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_131]
    at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:695) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:366) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:650) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:554) [craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131]
Caused by: java.lang.ArrayIndexOutOfBoundsException: 1
    at me.Blocker.Blocker.onCommand(Blocker.java:86) ~[?:?]
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[craftbukkit-1.12.jar:git-Bukkit-9a82fa7]
    ... 15 more