Every time I do a command in my server it says this " AN internal error occurred while attempting to perform this command"
CONSOLE :
> [10:13:54 ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing '/wand' in com.sk89q.bukkit.util.DynamicPluginCommand(/wand)
at me.incomprehendable.dev.pwp.FakeSimpleCommandMap.dispatch(FakeSimpleCommandMap.java:102) ~[?:?]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.dispatchCommand(CraftServer.java:648) ~[minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at net.minecraft.server.v1_12_R1.PlayerConnection.handleCommand(PlayerConnection.java:1397) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1232) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:45) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:1) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at net.minecraft.server.v1_12_R1.PlayerConnectionUtils$1.run(SourceFile:13) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_222]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_222]
at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:748) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:406) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:679) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:577) [minecraft_server.jar:git-Spigot-2cf50f0-2b93d83]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_222]
Caused by: java.lang.NoClassDefFoundError: org/bukkit/util/Java15Compat
at me.incomprehendable.dev.pwp.FakeSimpleCommandMap.dispatch(FakeSimpleCommandMap.java:98) ~[?:?]
... 14 more
