[18:34:25 ERROR]: Could not pass event PlayerCommandPreprocessEvent to TAB v2.4.4
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:302) ~[papermc.jar:git-PaperSpigot-"4c7641d"]
        at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:78) ~[papermc.jar:git-PaperSpigot-"4c7641d"]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[papermc.jar:git-PaperSpigot-"4c7641d"]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:517) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:502) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PlayerConnection.handleCommand(PlayerConnection.java:1181) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:1001) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:45) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:1) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_211]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_211]
        at net.minecraft.server.v1_8_R3.SystemUtils.a(SourceFile:44) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:774) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:378) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:713) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:616) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_211]
Caused by: java.lang.NullPointerException
        at me.neznamy.tab.bukkit.Main.unload(Main.java:173) ~[?:?]
        at me.neznamy.tab.bukkit.TabCommand.onCommand(TabCommand.java:127) ~[?:?]
        at me.neznamy.tab.bukkit.Main.a(Main.java:393) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_211]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_211]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_211]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_211]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:300) ~[papermc.jar:git-PaperSpigot-"4c7641d"]
        ... 17 more
[18:34:25 ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'tab' in plugin TAB v2.4.4
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:47) ~[papermc.jar:git-PaperSpigot-"4c7641d"]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:146) ~[papermc.jar:git-PaperSpigot-"4c7641d"]
        at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchCommand(CraftServer.java:666) ~[papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PlayerConnection.handleCommand(PlayerConnection.java:1189) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:1001) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:45) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:1) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_211]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_211]
        at net.minecraft.server.v1_8_R3.SystemUtils.a(SourceFile:44) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:774) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:378) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:713) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:616) [papermc.jar:git-PaperSpigot-"4c7641d"]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_211]
Caused by: java.lang.NullPointerException
        at me.neznamy.tab.bukkit.Main.unload(Main.java:173) ~[?:?]
        at me.neznamy.tab.bukkit.TabCommand.onCommand(TabCommand.java:127) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:45) ~[papermc.jar:git-PaperSpigot-"4c7641d"]
        ... 15 more