... 15 more
[23:10:15 ERROR]: Could not pass event InventoryClickEvent to CTF v1.0 Dev
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at net.minecraft.server.v1_9_R1.PlayerConnection.a(PlayerConnection.java:1852) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at net.minecraft.server.v1_9_R1.PacketPlayInWindowClick.a(SourceFile:33) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at net.minecraft.server.v1_9_R1.PacketPlayInWindowClick.a(SourceFile:10) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at net.minecraft.server.v1_9_R1.PlayerConnectionUtils$1.run(SourceFile:13) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_77]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_77]
        at net.minecraft.server.v1_9_R1.SystemUtils.a(SourceFile:45) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at net.minecraft.server.v1_9_R1.MinecraftServer.D(MinecraftServer.java:721) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at net.minecraft.server.v1_9_R1.DedicatedServer.D(DedicatedServer.java:400) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at net.minecraft.server.v1_9_R1.MinecraftServer.C(MinecraftServer.java:660) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at net.minecraft.server.v1_9_R1.MinecraftServer.run(MinecraftServer.java:559) [craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_77]
Caused by: java.lang.NullPointerException
        at de.microsamp.twerion.shop.ShopListener.onInvInteract(ShopListener.java:28) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_77]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_77]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_77]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_77]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[craftbukkit-1.9.2.jar:git-Spigot-944aa20-8d16fc0]
        ... 15 more