Cant create commands

[G0Shark]

I tried to create command, but its dont working, pls help

using CounterStrikeSharp.API;
using CounterStrikeSharp.API.Core;
using CounterStrikeSharp.API.Core.Attributes.Registration;
using CounterStrikeSharp.API.Modules.Commands;

namespace HelloWorldPlugin;
public class HelloWorldPlugin : BasePlugin
{
    public override string ModuleName => "Hello World Plugin";

    public override string ModuleVersion => "0.0.1";

    public override void Load(bool hotReload)
{
    AddCommand("css_hello", "testing", (player, info) =>
    {
        if (player == null) return;
        Server.ExecuteCommand("say hi");
    });
}

}