[14:34:53 WARN]: java.lang.ClassCastException: class org.bukkit.craftbukkit.v1_16_R3.entity.CraftPlayer cannot be cast to class org.bukkit.inventory.Inventory (org.bukkit.craftbukkit.v1_16_R3.entity.CraftPlayer and org.bukkit.inventory.Inventory are in unnamed module of loader 'app')
[14:34:53 WARN]:        at vb.$plugin.PluginMain.onCommand(PluginMain.java:53)
[14:34:53 WARN]:        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:45)
[14:34:53 WARN]:        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:159)
[14:34:53 WARN]:        at org.bukkit.craftbukkit.v1_16_R3.CraftServer.dispatchCommand(CraftServer.java:807)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.PlayerConnection.handleCommand(PlayerConnection.java:2021)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.PlayerConnection.c(PlayerConnection.java:1832)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.PlayerConnection.a(PlayerConnection.java:1785)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.PacketPlayInChat.a(PacketPlayInChat.java:47)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.PacketPlayInChat.a(PacketPlayInChat.java:5)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.PlayerConnectionUtils.lambda$ensureMainThread$1(PlayerConnectionUtils.java:23)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.TickTask.run(SourceFile:18)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeTask(IAsyncTaskHandler.java:136)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeNext(IAsyncTaskHandler.java:109)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.MinecraftServer.bb(MinecraftServer.java:1132)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.MinecraftServer.executeNext(MinecraftServer.java:1125)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.awaitTasks(IAsyncTaskHandler.java:119)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.MinecraftServer.a(MinecraftServer.java:1199)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.MinecraftServer.w(MinecraftServer.java:996)
[14:34:53 WARN]:        at net.minecraft.server.v1_16_R3.MinecraftServer.lambda$a$0(MinecraftServer.java:173)
[14:34:53 WARN]:        at java.base/java.lang.Thread.run(Thread.java:829)