Bukkit

[SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'buy' in plugin DynamicShop v1.46
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:42)
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:166)
    at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:479)
    at net.minecraft.server.NetServerHandler.handleCommand(NetServerHandler.java:821)
    at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:781)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:764)
    at net.minecraft.server.Packet3Chat.handle(Packet3Chat.java:34)
    at net.minecraft.server.NetworkManager.b(NetworkManager.java:229)
    at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:113)
    at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:78)
    at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:567)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:459)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
Caused by: java.lang.NullPointerException
    at me.zylinder.dynamicshop.PlayerHandler.checkInventory(PlayerHandler.java:137)
    at me.zylinder.dynamicshop.TransactionHandler.buyGlobal(TransactionHandler.java:85)
    at me.zylinder.dynamicshop.DynamicShopPlayerListener.onCommand(DynamicShopPlayerListener.java:122)
    at me.zylinder.dynamicshop.DynamicShop.onCommand(DynamicShop.java:110)
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:40)
    ... 12 more

Using Latest DynamicShop.