WorldGuard nullPointerException

Hello, i have a problem with WorldGuard 6.2.2 , i selected a region with world edit, and do the command /region define [name] and i keep getting an error saying "An unexpected error occurred! Please see the server console"
in the console i have this :
[09:28:46] [Server thread/INFO]: VacheMeuh issued server command: /region define test
[09:28:46] [Server thread/WARN]: [WorldGuard] WorldGuard encountered an unexpected error
java.lang.NullPointerException: null
at com.sk89q.worldguard.bukkit.RegionContainer.getSaveFailures(RegionContainer.java:254) ~[worldguard-bukkit-6.2.2.jar:?]
at com.sk89q.worldguard.bukkit.commands.region.RegionCommandsBase.warnAboutSaveFailures(RegionCommandsBase.java:298) ~[worldguard-bukkit-6.2.2.jar:?]
at com.sk89q.worldguard.bukkit.commands.region.RegionCommands.define(RegionCommands.java:107) ~[worldguard-bukkit-6.2.2.jar:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_144]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_144]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_144]
at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_144]
at com.sk89q.minecraft.util.commands.CommandsManager.invokeMethod(CommandsManager.java:528) ~[worldedit-bukkit-6.1.9.jar:?]
at com.sk89q.minecraft.util.commands.CommandsManager.executeMethod(CommandsManager.java:516) ~[worldedit-bukkit-6.1.9.jar:?]
at com.sk89q.minecraft.util.commands.CommandsManager.executeMethod(CommandsManager.java:471) ~[worldedit-bukkit-6.1.9.jar:?]
at com.sk89q.minecraft.util.commands.CommandsManager.execute(CommandsManager.java:409) ~[worldedit-bukkit-6.1.9.jar:?]
at com.sk89q.worldguard.bukkit.WorldGuardPlugin.onCommand(WorldGuardPlugin.java:285) [worldguard-bukkit-6.2.2.jar:?]
at com.sk89q.bukkit.util.DynamicPluginCommand.execute(DynamicPluginCommand.java:54) [worldedit-bukkit-6.1.9.jar:?]
at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:140) [minecraft_server.jar:git-Bukkit-2b93d83]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.dispatchCommand(CraftServer.java:628) [minecraft_server.jar:git-Bukkit-2b93d83]
at net.minecraft.server.v1_12_R1.PlayerConnection.handleCommand(PlayerConnection.java:1338) [minecraft_server.jar:git-Bukkit-2b93d83]
at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1198) [minecraft_server.jar:git-Bukkit-2b93d83]
at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(SourceFile:37) [minecraft_server.jar:git-Bukkit-2b93d83]
at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(SourceFile:9) [minecraft_server.jar:git-Bukkit-2b93d83]
at net.minecraft.server.v1_12_R1.PlayerConnectionUtils$1.run(SourceFile:13) [minecraft_server.jar:git-Bukkit-2b93d83]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_144]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_144]
at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) [minecraft_server.jar:git-Bukkit-2b93d83]
at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:696) [minecraft_server.jar:git-Bukkit-2b93d83]
at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:371) [minecraft_server.jar:git-Bukkit-2b93d83]
at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:651) [minecraft_server.jar:git-Bukkit-2b93d83]
at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:555) [minecraft_server.jar:git-Bukkit-2b93d83]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_144]

Hope you'll help me, i need to open my server as fast as possible.