BossShop v2.0.5

[13:11:59] [Server thread/ERROR]: Could not pass event InventoryClickEvent to BossShop v2.0.5
org.bukkit.event.EventException
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:294) ~[spigot_V1383.jar:git-Spigot-1383]
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot_V1383.jar:git-Spigot-1383]
    at org.bukkit.plugin.TimedRegisteredListener.callEvent(TimedRegisteredListener.java:47) ~[spigot_V1383.jar:git-Spigot-1383]
    at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot_V1383.jar:git-Spigot-1383]
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.PlayerConnection.a(PlayerConnection.java:1403) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.PacketPlayInWindowClick.a(SourceFile:32) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.PacketPlayInWindowClick.handle(SourceFile:10) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.NetworkManager.a(NetworkManager.java:148) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.ServerConnection.c(ServerConnection.java:77) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.MinecraftServer.v(MinecraftServer.java:705) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.DedicatedServer.v(DedicatedServer.java:273) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.MinecraftServer.u(MinecraftServer.java:568) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.MinecraftServer.run(MinecraftServer.java:474) [spigot_V1383.jar:git-Spigot-1383]
    at net.minecraft.server.v1_7_R2.ThreadServerApplication.run(SourceFile:618) [spigot_V1383.jar:git-Spigot-1383]
Caused by: java.lang.ClassCastException: java.lang.Integer cannot be cast to org.black_ixx.bossshop.core.BSCustomLink
    at org.black_ixx.bossshop.core.BSBuy.giveReward(BSBuy.java:358) ~[?:?]
    at org.black_ixx.bossshop.listeners.InventoryListener.purchase(InventoryListener.java:134) ~[?:?]
    at sun.reflect.GeneratedMethodAccessor127.invoke(Unknown Source) ~[?:?]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_51]
    at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_51]
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:292) ~[spigot_V1383.jar:git-Spigot-1383]
    ... 14 more