Skellet packet analysis not working!

[Rock]

I am coding an extensive packet analysis anticheat right now. All of a sudden, analyzing packets isnt working... I am using Skellet and 1.12.2

I try to get packet fields and this is in console

[23:23:20 ERROR]: [Skript] c is not a field for packet PacketPlayInBlockPlace
[23:23:20 ERROR]: [Skript] e is not a field for packet PacketPlayInBlockPlace
[23:23:20 ERROR]: [Skript] f is not a field for packet PacketPlayInBlockPlace
[23:23:20 ERROR]: [Skript] g is not a field for packet PacketPlayInBlockPlace
[23:23:20 ERROR]: [Skript] c is not a field for packet PacketPlayInBlockPlace
[23:23:20 ERROR]: [Skript] e is not a field for packet PacketPlayInBlockPlace
[23:23:20 ERROR]: [Skript] f is not a field for packet PacketPlayInBlockPlace
[23:23:20 ERROR]: [Skript] g is not a field for packet PacketPlayInBlockPlace

[23:24:54 ERROR]: Could not pass event EvtPacket to Skript v2.3.7
java.util.ConcurrentModificationException: null
        at java.util.ArrayList$Itr.checkForComodification(Unknown Source) ~[?:1.8.0_221]
        at java.util.ArrayList$Itr.next(Unknown Source) ~[?:1.8.0_221]
        at ch.njol.skript.SkriptEventHandler$3.next(SkriptEventHandler.java:87) ~[?:?]
        at ch.njol.skript.SkriptEventHandler$3.next(SkriptEventHandler.java:1) ~[?:?]
        at ch.njol.skript.SkriptEventHandler.check(SkriptEventHandler.java:145) ~[?:?]
        at ch.njol.skript.SkriptEventHandler$1.execute(SkriptEventHandler.java:110) ~[?:?]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:500) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:485) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at com.gmail.thelimeglass.Utils.Packets.PacketListener$1.write(PacketListener.java:60) [Skellett.jar:?]
        at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:738) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.channel.AbstractChannelHandlerContext.invokeWriteAndFlush(AbstractChannelHandlerContext.java:801) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:814) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.channel.AbstractChannelHandlerContext.writeAndFlush(AbstractChannelHandlerContext.java:794) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.channel.AbstractChannelHandlerContext.writeAndFlush(AbstractChannelHandlerContext.java:831) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.channel.DefaultChannelPipeline.writeAndFlush(DefaultChannelPipeline.java:1071) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.channel.AbstractChannel.writeAndFlush(AbstractChannel.java:300) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at net.minecraft.server.v1_12_R1.NetworkManager$4.run(NetworkManager.java:200) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:404) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:463) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:884) [spigot-1.12.2.jar:git-Spigot-dcd1643-e60fc34]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_221]

Any help?