SetRank Error

[SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'setr
ank' in plugin SetRank v1.11
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:37)
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:12
9)
        at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:3
20)
        at net.minecraft.server.NetServerHandler.handleCommand(NetServerHandler.
java:713)
        at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:677)

        at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:670)
        at net.minecraft.server.Packet3Chat.a(Packet3Chat.java:33)
        at net.minecraft.server.NetworkManager.b(NetworkManager.java:226)
        at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:85)
        at net.minecraft.server.NetworkListenThread.a(SourceFile:105)
        at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:451)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:361)
        at net.minecraft.server.ThreadServerApplication.run(SourceFile:422)
Caused by: java.lang.NoSuchMethodError: com.nijiko.permissions.PermissionHandler
.getUserObject(Ljava/lang/String;Ljava/lang/String;)Lcom/nijiko/permissions/User
;
        at com.Baummann.SetRank.SetRank.SetRank.canAddOrRemoveParent(SetRank.jav
a:68)
        at com.Baummann.SetRank.SetRank.SetRank.onCommand(SetRank.java:131)
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:35)
        ... 12 more