Foxguard error

[13:35:48] [Server thread/ERROR] [Sponge]: Error occurred while executing command 'fg create handler mainspawn basic plugandplay' for source EntityPlayerMP['comdarksider'/389, l='world', x=957.92, y=69.00, z=461.94]: org/spongepowered/api/event/SpongeEventFactoryUtils
java.lang.NoClassDefFoundError: org/spongepowered/api/event/SpongeEventFactoryUtils
        at net.foxdenstudio.sponge.foxguard.plugin.event.util.FGEventFactory.createFGUpdateObjectEvent(FGEventFactory.java:43) ~[FGEventFactory.class:?]
        at net.foxdenstudio.sponge.foxguard.plugin.FGManager.addHandler(FGManager.java:363) ~[FGManager.class:?]
        at net.foxdenstudio.sponge.foxguard.plugin.command.CommandCreate.process(CommandCreate.java:206) ~[CommandCreate.class:?]
        at net.foxdenstudio.sponge.foxcore.plugin.command.FCCommandDispatcher.process(FCCommandDispatcher.java:235) ~[FCCommandDispatcher.class:?]
        at org.spongepowered.api.command.dispatcher.SimpleDispatcher.process(SimpleDispatcher.java:336) ~[SimpleDispatcher.class:1.10.2-2221-5.1.0-BETA-2210]
        at org.spongepowered.common.command.SpongeCommandManager.process(SpongeCommandManager.java:295) ~[SpongeCommandManager.class:1.10.2-2221-5.1.0-BETA-2210]
        at net.minecraft.command.ServerCommandManager.func_71556_a(SourceFile:1083) ~[bd.class:?]
        at net.minecraft.network.NetHandlerPlayServer.func_147361_d(NetHandlerPlayServer.java:913) ~[me.class:?]
        at net.minecraft.network.NetHandlerPlayServer.func_147354_a(NetHandlerPlayServer.java:892) ~[me.class:?]
        at net.minecraft.network.play.client.CPacketChatMessage.func_148833_a(SourceFile:37) ~[im.class:?]
        at net.minecraft.network.play.client.CPacketChatMessage.func_148833_a(SourceFile:9) ~[im.class:?]
        at org.spongepowered.common.network.PacketUtil.lambda$onProcessPacket$0(PacketUtil.java:158) ~[PacketUtil.class:1.10.2-2221-5.1.0-BETA-2210]
        at org.spongepowered.common.event.tracking.CauseTracker.switchToPhase(CauseTracker.java:156) [CauseTracker.class:1.10.2-2221-5.1.0-BETA-2210]
        at org.spongepowered.common.network.PacketUtil.onProcessPacket(PacketUtil.java:157) [PacketUtil.class:1.10.2-2221-5.1.0-BETA-2210]
        at net.minecraft.network.PacketThreadUtil$1.redirect$onProcessPacket$zjf000(SourceFile:539) [fl$1.class:?]
        at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) [fl$1.class:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_121]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_121]
        at net.minecraft.util.Util.func_181617_a(SourceFile:45) [h.class:?]
        at org.spongepowered.common.SpongeImplHooks.onUtilRunTask(SpongeImplHooks.java:235) [SpongeImplHooks.class:1.10.2-2221-5.1.0-BETA-2210]
        at net.minecraft.server.MinecraftServer.redirect$onRun$zhm000(MinecraftServer.java:3931) [MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:668) [MinecraftServer.class:?]
        at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:387) [ld.class:?]
        at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:613) [MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:471) [MinecraftServer.class:?]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_121]
Caused by: java.lang.ClassNotFoundException: org.spongepowered.api.event.SpongeEventFactoryUtils
        at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191) ~[launchwrapper-1.12.jar:?]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_121]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_121]
        ... 26 more
Caused by: java.lang.NullPointerException