null
org.bukkit.command.CommandException: Unhandled exception executing 'sell' in com.pablo67340.guishop.commands.SellCommand(sell)
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:169) ~[patched_1.16.1.jar:git-Paper-135]
        at org.bukkit.craftbukkit.v1_16_R1.CraftServer.dispatchCommand(CraftServer.java:794) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.PlayerConnection.handleCommand(PlayerConnection.java:1910) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.PlayerConnection.a(PlayerConnection.java:1721) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.PacketPlayInChat.a(PacketPlayInChat.java:47) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.PacketPlayInChat.a(PacketPlayInChat.java:5) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.PlayerConnectionUtils.lambda$ensureMainThread$1(PlayerConnectionUtils.java:23) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.TickTask.run(SourceFile:18) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.IAsyncTaskHandler.executeTask(IAsyncTaskHandler.java:136) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.IAsyncTaskHandler.executeNext(IAsyncTaskHandler.java:109) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.MinecraftServer.aZ(MinecraftServer.java:1137) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.MinecraftServer.executeNext(MinecraftServer.java:1130) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.IAsyncTaskHandler.awaitTasks(IAsyncTaskHandler.java:119) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.MinecraftServer.sleepForTick(MinecraftServer.java:1091) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.MinecraftServer.v(MinecraftServer.java:1005) ~[patched_1.16.1.jar:git-Paper-135]
        at net.minecraft.server.v1_16_R1.MinecraftServer.lambda$a$0(MinecraftServer.java:177) ~[patched_1.16.1.jar:git-Paper-135]
        at java.lang.Thread.run(Thread.java:834) [?:?]
Caused by: java.lang.ClassCastException: class com.pablo67340.guishop.commands.GuishopUserCommand cannot be cast to class com.pablo67340.guishop.commands.GuishopUserCommand (com.pablo67340.guishop.commands.GuishopUserCommand is in unnamed module of loader org.bukkit.plugin.java.PluginClassLoader @7c4db82f; com.pablo67340.guishop.commands.GuishopUserCommand is in unnamed module of loader org.bukkit.plugin.java.PluginClassLoader @2ab837d4)
        at com.pablo67340.guishop.Main.getUserCommands(Main.java:235) ~[?:?]
        at com.pablo67340.guishop.commands.SellCommand.execute(SellCommand.java:24) ~[?:?]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:159) ~[patched_1.16.1.jar:git-Paper-135]