[20:18:06 ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'prefix' in plugin MoonPrefix v1.5.3
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:48) ~[paper.jar:git-Paper-629]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:151) ~[paper.jar:git-Paper-629]
        at org.bukkit.craftbukkit.v1_13_R2.CraftServer.dispatchCommand(CraftServer.java:734) ~[paper.jar:git-Paper-629]
        at net.minecraft.server.v1_13_R2.PlayerConnection.handleCommand(PlayerConnection.java:1783) ~[paper.jar:git-Paper-629]
        at net.minecraft.server.v1_13_R2.PlayerConnection.a(PlayerConnection.java:1591) ~[paper.jar:git-Paper-629]
        at net.minecraft.server.v1_13_R2.PacketPlayInChat.a(PacketPlayInChat.java:45) ~[paper.jar:git-Paper-629]
        at net.minecraft.server.v1_13_R2.PacketPlayInChat.a(PacketPlayInChat.java:5) ~[paper.jar:git-Paper-629]
        at net.minecraft.server.v1_13_R2.PlayerConnectionUtils.lambda$ensureMainThread$0(PlayerConnectionUtils.java:15) ~[paper.jar:git-Paper-629]
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[?:1.8.0_171]
        at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_171]
        at net.minecraft.server.v1_13_R2.SystemUtils.a(SystemUtils.java:108) ~[paper.jar:git-Paper-629]
        at net.minecraft.server.v1_13_R2.MinecraftServer.b(MinecraftServer.java:1018) ~[paper.jar:git-Paper-629]
        at net.minecraft.server.v1_13_R2.DedicatedServer.b(DedicatedServer.java:439) ~[paper.jar:git-Paper-629]
        at net.minecraft.server.v1_13_R2.MinecraftServer.a(MinecraftServer.java:940) ~[paper.jar:git-Paper-629]
        at net.minecraft.server.v1_13_R2.MinecraftServer.run(MinecraftServer.java:837) ~[paper.jar:git-Paper-629]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_171]
Caused by: java.lang.BootstrapMethodError: call site initialization exception
        at java.lang.invoke.CallSite.makeSite(CallSite.java:341) ~[?:1.8.0_171]
        at java.lang.invoke.MethodHandleNatives.linkCallSiteImpl(MethodHandleNatives.java:307) ~[?:1.8.0_171]
        at java.lang.invoke.MethodHandleNatives.linkCallSite(MethodHandleNatives.java:297) ~[?:1.8.0_171]
        at space.moonstudio.moonprefix.Menu.open(Menu.java:84) ~[?:?]
        at space.moonstudio.moonprefix.cmd.onCommand(cmd.java:30) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[paper.jar:git-Paper-629]
        ... 15 more
Caused by: java.lang.NullPointerException
        at java.lang.invoke.MethodHandles$Lookup.unreflect(MethodHandles.java:1182) ~[?:1.8.0_171]
        at space.moonstudio.moonprefix.Menu.CR(Menu.java) ~[?:?]
        at java.lang.invoke.CallSite.makeSite(CallSite.java:283) ~[?:1.8.0_171]
        at java.lang.invoke.MethodHandleNatives.linkCallSiteImpl(MethodHandleNatives.java:307) ~[?:1.8.0_171]
        at java.lang.invoke.MethodHandleNatives.linkCallSite(MethodHandleNatives.java:297) ~[?:1.8.0_171]
        at space.moonstudio.moonprefix.Menu.open(Menu.java:84) ~[?:?]
        at space.moonstudio.moonprefix.cmd.onCommand(cmd.java:30) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[paper.jar:git-Paper-629]
        ... 15 more
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