Could not pass event PlayerInteractEvent to LockettePro v2.8.1

[andris155]

[20:06:37] [Server thread/ERROR]: Could not pass event PlayerInteractEvent to LockettePro v2.8.1
org.bukkit.event.EventException: null
	at org.bukkit.plugin.EventExecutor$1.execute(EventExecutor.java:46) ~[patched_1.12.jar:git-Paper-1134]
	at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:74) ~[patched_1.12.jar:git-Paper-1134]
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[patched_1.12.jar:git-Paper-1134]
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:514) ~[patched_1.12.jar:git-Paper-1134]
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:499) ~[patched_1.12.jar:git-Paper-1134]
	at org.bukkit.craftbukkit.v1_12_R1.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:235) ~[patched_1.12.jar:git-Paper-1134]
	at net.minecraft.server.v1_12_R1.PlayerInteractManager.a(PlayerInteractManager.java:448) ~[patched_1.12.jar:git-Paper-1134]
	at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:948) ~[patched_1.12.jar:git-Paper-1134]
	at net.minecraft.server.v1_12_R1.PacketPlayInUseItem.a(PacketPlayInUseItem.java:37) ~[patched_1.12.jar:git-Paper-1134]
	at net.minecraft.server.v1_12_R1.PacketPlayInUseItem.a(PacketPlayInUseItem.java:5) ~[patched_1.12.jar:git-Paper-1134]
	at net.minecraft.server.v1_12_R1.PlayerConnectionUtils.lambda$ensureMainThread$0(PlayerConnectionUtils.java:14) ~[patched_1.12.jar:git-Paper-1134]
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_131]
	at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_131]
	at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) [patched_1.12.jar:git-Paper-1134]
	at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:842) [patched_1.12.jar:git-Paper-1134]
	at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:423) [patched_1.12.jar:git-Paper-1134]
	at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:766) [patched_1.12.jar:git-Paper-1134]
	at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:664) [patched_1.12.jar:git-Paper-1134]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131]
Caused by: java.lang.ClassCastException: org.bukkit.craftbukkit.v1_12_R1.block.CraftBlockState cannot be cast to org.bukkit.block.Sign
	at me.crafter.mc.lockettepro.Utils.updateSign(Utils.java:85) ~[?:?]
	at me.crafter.mc.lockettepro.Utils.putSignOn(Utils.java:61) ~[?:?]
	at me.crafter.mc.lockettepro.BlockPlayerListener.onPlayerQuickLockChest(BlockPlayerListener.java:63) ~[?:?]
	at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor628.execute(Unknown Source) ~[?:?]
	at org.bukkit.plugin.EventExecutor$1.execute(EventExecutor.java:44) ~[patched_1.12.jar:git-Paper-1134]
	... 18 more

[connection-lost]

Good catch, but can you please tell me how to replicate this issue, like how can you make this happen?