[17:12:22 INFO]: nahventure issued server command: /sellstick give nahventure 1 1
[17:12:22 ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'sellstick' in plugin SellStick v8.0.5
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:151) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at org.bukkit.craftbukkit.v1_12_R1.CraftServer.dispatchCommand(CraftServer.java:685) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at net.minecraft.server.v1_12_R1.PlayerConnection.handleCommand(PlayerConnection.java:1472) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1277) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:45) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:5) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at net.minecraft.server.v1_12_R1.PlayerConnectionUtils.lambda$ensureMainThread$0(PlayerConnectionUtils.java:14) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_171]
        at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_171]
        at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) [PaperSpigot-latest.jar:git-Paper-1471]
        at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:843) [PaperSpigot-latest.jar:git-Paper-1471]
        at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:427) [PaperSpigot-latest.jar:git-Paper-1471]
        at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:767) [PaperSpigot-latest.jar:git-Paper-1471]
        at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:665) [PaperSpigot-latest.jar:git-Paper-1471]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_171]
Caused by: java.lang.NoClassDefFoundError: net/minecraft/server/v1_8_R3/NBTBase
        at com.acropolismc.play.sellstick.SellStickCommand.onCommand(SellStickCommand.java:82) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[PaperSpigot-latest.jar:git-Paper-1471]
        ... 15 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_8_R3.NBTBase
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:109) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:104) ~[PaperSpigot-latest.jar:git-Paper-1471]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_171]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_171]
        at com.acropolismc.play.sellstick.SellStickCommand.onCommand(SellStickCommand.java:82) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[PaperSpigot-latest.jar:git-Paper-1471]
        ... 15 more