/createtown don't work

[21:45:00] [Server thread/ERROR] [Sponge]: Error occurred while executing command 'createtown 123' for source EntityPlayerMP['jules552'/395, l='world', x=-247,84, y=99,00, z=103,72]: null
java.lang.NullPointerException
        at io.github.hsyyid.polis.utils.ConfigManager.getTeams(ConfigManager.java:30) ~[ConfigManager.class:0.4]
        at io.github.hsyyid.polis.cmdexecutors.CreateTownExecutor.execute(CreateTownExecutor.java:27) ~[CreateTownExecutor.class:0.4]
        at org.spongepowered.api.util.command.spec.CommandSpec.process(CommandSpec.java:334) ~[CommandSpec.class:1.8-1530-2.1-DEV-770]
        at org.spongepowered.api.util.command.dispatcher.SimpleDispatcher.process(SimpleDispatcher.java:340) ~[SimpleDispatcher.class:1.8-1530-2.1-DEV-770]
        at org.spongepowered.api.service.command.SimpleCommandService.process(SimpleCommandService.java:250) [SimpleCommandService.class:1.8-1530-2.1-DEV-770]
        at net.minecraft.command.ServerCommandManager.func_71556_a(SourceFile:80) [cl.class:?]
        at net.minecraft.network.NetHandlerPlayServer.func_147361_d(NetHandlerPlayServer.java:812) [rj.class:?]
        at net.minecraft.network.NetHandlerPlayServer.func_147354_a(NetHandlerPlayServer.java:791) [rj.class:?]
        at net.minecraft.network.play.client.C01PacketChatMessage.func_180757_a(SourceFile:37) [lu.class:?]
        at net.minecraft.network.play.client.C01PacketChatMessage.func_148833_a(SourceFile:9) [lu.class:?]
        at net.minecraft.network.PacketThreadUtil$1.onProcessPacket(SourceFile:59) [ih.class:?]
        at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) [ih.class:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_66]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_66]
        at net.minecraftforge.fml.common.FMLCommonHandler.callFuture(FMLCommonHandler.java:714) [FMLCommonHandler.class:?]
        at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:656) [MinecraftServer.class:?]
        at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:364) [po.class:?]
        at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:598) [MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:478) [MinecraftServer.class:?]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_66]