[21:05:56] [Server thread/ERROR]: Could not pass event PlayerMoveEvent to Maze v0.5-SNAPSHOT

org.bukkit.event.EventException

	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at net.minecraft.server.v1_11_R1.PlayerConnection.a(PlayerConnection.java:615) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at net.minecraft.server.v1_11_R1.PacketPlayInFlying.a(SourceFile:126) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at net.minecraft.server.v1_11_R1.PacketPlayInFlying$PacketPlayInPositionLook.a(SourceFile:18) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at net.minecraft.server.v1_11_R1.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_72]

	at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_72]

	at net.minecraft.server.v1_11_R1.SystemUtils.a(SourceFile:46) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at net.minecraft.server.v1_11_R1.MinecraftServer.D(MinecraftServer.java:739) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at net.minecraft.server.v1_11_R1.DedicatedServer.D(DedicatedServer.java:399) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at net.minecraft.server.v1_11_R1.MinecraftServer.C(MinecraftServer.java:675) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at net.minecraft.server.v1_11_R1.MinecraftServer.run(MinecraftServer.java:574) [spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

	at java.lang.Thread.run(Thread.java:745) [?:1.8.0_72]

Caused by: java.util.ConcurrentModificationException

	at java.util.HashMap$HashIterator.nextNode(HashMap.java:1429) ~[?:1.8.0_72]

	at java.util.HashMap$KeyIterator.next(HashMap.java:1453) ~[?:1.8.0_72]

	at eu.manuelgu.maze.listeners.PlayerListener.sendCoinRemove(PlayerListener.java:213) ~[?:?]

	at eu.manuelgu.maze.listeners.PlayerListener.onPlayerMove(PlayerListener.java:117) ~[?:?]

	at sun.reflect.GeneratedMethodAccessor93.invoke(Unknown Source) ~[?:?]

	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_72]

	at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_72]

	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:302) ~[spigot-1.11.2.jar:git-Spigot-7d78b81-e232e15]

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