HyperMerchant Error

[19:58:21] [Server thread/ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'clerk' in plugin HyperMerchant v1.56.1
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[PluginCommand.class:git-Cauldron-MCPC-Plus-1.7.10-1.1207.01.198]
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:181) ~[SimpleCommandMap.class:git-Cauldron-MCPC-Plus-1.7.10-1.1207.01.198]
	at org.bukkit.craftbukkit.v1_7_R4.CraftServer.dispatchCommand(CraftServer.java:717) ~[CraftServer.class:git-Cauldron-MCPC-Plus-1.7.10-1.1207.01.198]
	at net.minecraft.network.NetHandlerPlayServer.func_147361_d(NetHandlerPlayServer.java:1347) [nh.class:?]
	at net.minecraft.network.NetHandlerPlayServer.func_147354_a(NetHandlerPlayServer.java:1129) [nh.class:?]
	at net.minecraft.network.play.client.C01PacketChatMessage.func_148833_a(C01PacketChatMessage.java:38) [ir.class:?]
	at net.minecraft.network.play.client.C01PacketChatMessage.func_148833_a(C01PacketChatMessage.java:53) [ir.class:?]
	at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:244) [ej.class:?]
	at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:173) [nc.class:?]
	at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:980) [MinecraftServer.class:?]
	at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:423) [lt.class:?]
	at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:798) [MinecraftServer.class:?]
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:658) [MinecraftServer.class:?]
	at java.lang.Thread.run(Unknown Source) [?:1.7.0_55]
Caused by: java.lang.NullPointerException
	at grokswell.hypermerchant.ClerkCommand.<init>(ClerkCommand.java:232) ~[?:?]
	at grokswell.hypermerchant.HyperMerchantPlugin.onCommand(HyperMerchantPlugin.java:273) ~[?:?]
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[PluginCommand.class:git-Cauldron-MCPC-Plus-1.7.10-1.1207.01.198]
	... 13 more
[19:58:46]