Error plugin Custom NPC

I created a plugin for my server that do /createnpc
He creates an NPC and right-clicks on it and writes "DID IT WORK?" But it does not work and it writes me an error in Console:

Code:

[16:01:40 ERROR]: Error occurred while enabling NPC v2.2 (Is it up to date?)
org.bukkit.plugin.IllegalPluginAccessException: Unable to find handler list for event me.kfir123116.NPC.Event.RightClickNPC. Static getHandlerList method required!
        at org.bukkit.plugin.SimplePluginManager.getRegistrationClass(SimplePluginManager.java:586) ~[spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at org.bukkit.plugin.SimplePluginManager.registerEvents(SimplePluginManager.java:528) ~[spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at me.kfir123116.NPC.Main.onEnable(Main.java:20) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:321) ~[spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:340) [spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:405) [spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugin(CraftServer.java:357) [spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at org.bukkit.craftbukkit.v1_8_R3.CraftServer.enablePlugins(CraftServer.java:317) [spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at net.minecraft.server.v1_8_R3.MinecraftServer.s(MinecraftServer.java:414) [spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at net.minecraft.server.v1_8_R3.MinecraftServer.k(MinecraftServer.java:378) [spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at net.minecraft.server.v1_8_R3.MinecraftServer.a(MinecraftServer.java:333) [spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:263) [spigot46.jar:git-Spigot-21fe707-e1ebe52]
        at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:525) [spigot46.jar:git-Spigot-21fe707-e1ebe52]

Link to github​

 

@timtower

What event?

 

Yes but I do not know what that means