org.bukkit.command.CommandException: Unhandled exception executing command 'syncinv' in plugin InventorySyncer v1.0
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:47) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:149) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at org.bukkit.craftbukkit.v1_16_R3.CraftServer.dispatchCommand(CraftServer.java:763) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.PlayerConnection.handleCommand(PlayerConnection.java:1788) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.PlayerConnection.c(PlayerConnection.java:1631) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.PlayerConnection.a(PlayerConnection.java:1584) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.PacketPlayInChat.a(PacketPlayInChat.java:47) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.PacketPlayInChat.a(PacketPlayInChat.java:1) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.PlayerConnectionUtils.lambda$0(PlayerConnectionUtils.java:19) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.TickTask.run(SourceFile:18) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeTask(SourceFile:144) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeNext(SourceFile:118) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.MinecraftServer.bb(MinecraftServer.java:942) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.MinecraftServer.executeNext(MinecraftServer.java:935) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.awaitTasks(SourceFile:127) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.MinecraftServer.sleepForTick(MinecraftServer.java:919) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.MinecraftServer.w(MinecraftServer.java:851) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at net.minecraft.server.v1_16_R3.MinecraftServer.lambda$0(MinecraftServer.java:164) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	at java.lang.Thread.run(Unknown Source) [?:1.8.0_301]
Caused by: java.lang.NumberFormatException: For input string: ""
	at java.lang.NumberFormatException.forInputString(Unknown Source) ~[?:1.8.0_301]
	at java.lang.Integer.parseInt(Unknown Source) ~[?:1.8.0_301]
	at java.lang.Integer.parseInt(Unknown Source) ~[?:1.8.0_301]
	at fr.lebonniec.maxime.inventorysyncer.commands.CommandSyncInv.onCommand(CommandSyncInv.java:34) ~[?:?]
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:45) ~[spigot-1.16.5.jar:2991-Spigot-018b9a0-f3f3094]
	... 19 more