[22:52:32] [Server thread/ERROR]: Could not pass event PlayerInteractEvent to UhcCore v1.12.2
org.bukkit.event.EventException
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:302) ~[patched.jar:git-PaperSpigot-"4c7641d"]
    at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:74) ~[patched.jar:git-PaperSpigot-"4c7641d"]
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[patched.jar:git-PaperSpigot-"4c7641d"]
    at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:517) [patched.jar:git-PaperSpigot-"4c7641d"]
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:502) [patched.jar:git-PaperSpigot-"4c7641d"]
    at org.bukkit.craftbukkit.v1_8_R3.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:228) [patched.jar:git-PaperSpigot-"4c7641d"]
    at org.bukkit.craftbukkit.v1_8_R3.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:195) [patched.jar:git-PaperSpigot-"4c7641d"]
    at net.minecraft.server.v1_8_R3.PlayerInteractManager.a(PlayerInteractManager.java:107) [patched.jar:git-PaperSpigot-"4c7641d"]
    at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:626) [patched.jar:git-PaperSpigot-"4c7641d"]
    at net.minecraft.server.v1_8_R3.PacketPlayInBlockDig.a(SourceFile:40) [patched.jar:git-PaperSpigot-"4c7641d"]
    at net.minecraft.server.v1_8_R3.PacketPlayInBlockDig.a(SourceFile:10) [patched.jar:git-PaperSpigot-"4c7641d"]
    at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [patched.jar:git-PaperSpigot-"4c7641d"]
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_201]
    at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_201]
    at net.minecraft.server.v1_8_R3.SystemUtils.a(SourceFile:44) [patched.jar:git-PaperSpigot-"4c7641d"]
    at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:774) [patched.jar:git-PaperSpigot-"4c7641d"]
    at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:378) [patched.jar:git-PaperSpigot-"4c7641d"]
    at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:713) [patched.jar:git-PaperSpigot-"4c7641d"]
    at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:616) [patched.jar:git-PaperSpigot-"4c7641d"]
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_201]
Caused by: java.lang.NullPointerException
    at com.gmail.val59000mc.customitems.UhcItems.isCraftBookItem(UhcItems.java:253) ~[UHC-Core.jar:?]
    at com.gmail.val59000mc.listeners.ItemsListener.onRightClickItem(ItemsListener.java:55) ~[UHC-Core.jar:?]
    at sun.reflect.GeneratedMethodAccessor79.invoke(Unknown Source) ~[?:?]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_201]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_201]
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:300) ~[patched.jar:git-PaperSpigot-"4c7641d"]
    ... 19 more