NPE

Could not pass event InventoryClickEvent to Voting v1.1.2
org.bukkit.event.EventException: null
	at org.bukkit.plugin.EventExecutor$1.execute(EventExecutor.java:46) ~[patched_1.12.jar:git-Paper-1143]
	at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:78) ~[patched_1.12.jar:git-Paper-1143]
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[patched_1.12.jar:git-Paper-1143]
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:514) ~[patched_1.12.jar:git-Paper-1143]
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:499) ~[patched_1.12.jar:git-Paper-1143]
	at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1933) ~[patched_1.12.jar:git-Paper-1143]
	at net.minecraft.server.v1_12_R1.PacketPlayInWindowClick.a(SourceFile:33) ~[patched_1.12.jar:git-Paper-1143]
	at net.minecraft.server.v1_12_R1.PacketPlayInWindowClick.a(SourceFile:10) ~[patched_1.12.jar:git-Paper-1143]
	at net.minecraft.server.v1_12_R1.PlayerConnectionUtils.lambda$ensureMainThread$0(PlayerConnectionUtils.java:14) ~[patched_1.12.jar:git-Paper-1143]
	at java.util.concurrent.Executors$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-1143]
	at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:842) [patched_1.12.jar:git-Paper-1143]
	at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:423) [patched_1.12.jar:git-Paper-1143]
	at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:766) [patched_1.12.jar:git-Paper-1143]
	at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:664) [patched_1.12.jar:git-Paper-1143]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131]
Caused by: java.lang.NullPointerException
	at java.lang.String.replace(String.java:2240) ~[?:1.8.0_131]
	at gmail.Sobky.Voting.Core.Core.start(Core.java:40) ~[?:?]
	at gmail.Sobky.Voting.Core.Core.<init>(Core.java:31) ~[?:?]
	at gmail.Sobky.Voting.Voting.newCore(Voting.java:142) ~[?:?]
	at gmail.Sobky.Voting.Listeners.InventoryListeners.clickInInventory(InventoryListeners.java:79) ~[?:?]
	at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor6129.execute(Unknown Source) ~[?:?]
	at org.bukkit.plugin.EventExecutor$1.execute(EventExecutor.java:44) ~[patched_1.12.jar:git-Paper-1143]
	... 16 more