ArmoredElytra PrepareAnvilEvent

[12:46:07 ERROR]: Could not pass event PrepareAnvilEvent to ArmoredElytra v2.4.3
org.bukkit.event.EventException: null
        at org.bukkit.plugin.EventExecutor$2.execute(EventExecutor.java:72) ~[patched_1.13.1.jar:git-Paper-291]
        at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:78) ~[patched_1.13.1.jar:git-Paper-291]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[patched_1.13.1.jar:git-Paper-291]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:513) ~[patched_1.13.1.jar:git-Paper-291]
        at org.bukkit.craftbukkit.v1_13_R2.event.CraftEventFactory.callPrepareAnvilEvent(CraftEventFactory.java:1124) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.ContainerAnvil.d(ContainerAnvil.java:307) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.ContainerAnvil.a(ContainerAnvil.java:120) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.ContainerAnvil$1.update(ContainerAnvil.java:20) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.InventorySubcontainer.splitStack(InventorySubcontainer.java:89) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.Slot.a(SourceFile:102) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.Container.a(Container.java:281) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.PlayerConnection.a(PlayerConnection.java:2292) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.PacketPlayInWindowClick.a(SourceFile:33) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.PacketPlayInWindowClick.a(SourceFile:10) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.PlayerConnectionUtils.lambda$ensureMainThread$0(PlayerConnectionUtils.java:12) ~[patched_1.13.1.jar:git-Paper-291]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~[?:1.8.0_144]
        at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_144]
        at net.minecraft.server.v1_13_R2.SystemUtils.a(SourceFile:199) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.MinecraftServer.b(MinecraftServer.java:1018) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.DedicatedServer.b(DedicatedServer.java:434) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.MinecraftServer.a(MinecraftServer.java:945) ~[patched_1.13.1.jar:git-Paper-291]
        at net.minecraft.server.v1_13_R2.MinecraftServer.run(MinecraftServer.java:843) ~[patched_1.13.1.jar:git-Paper-291]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_144]
Caused by: java.lang.NumberFormatException: For input string: "d"
        at java.lang.NumberFormatException.forInputString(Unknown Source) ~[?:1.8.0_144]
        at java.lang.Integer.parseInt(Unknown Source) ~[?:1.8.0_144]
        at java.lang.Integer.parseInt(Unknown Source) ~[?:1.8.0_144]
        at nl.pim16aap2.armoredElytra.nms.NBTEditor_V1_13_R2.getArmorTier(NBTEditor_V1_13_R2.java:97) ~[?:?]
        at nl.pim16aap2.armoredElytra.handlers.EventHandlers.onAnvilInventoryOpen(EventHandlers.java:370) ~[?:?]
        at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor3.execute(Unknown Source) ~[?:?]
        at org.bukkit.plugin.EventExecutor$2.execute(EventExecutor.java:70) ~[patched_1.13.1.jar:git-Paper-291]
        ... 22 more