How to activate IHubContext service in ASP.NET Core MVC?

I have used signalR in my project. There is a hub that users can send notifications to each other. In login part of the project, I want to send notification to the admin when a user is signed in. I need to send this notification from controller, not client side. I tried:

//after dependancy injection
_hubContext.Clients.User(***).SendAsync("LoginIn", "text1", "text2", "text3");

The following error is shown:

InvalidOperationException: Unable to resolve service for type 'Microsoft.AspNetCore.SignalR.IHubContext' while attempting to activate 'CustomizedIdentity.Controllers.HomeController'.

I tried to register IHubContext in Services:

    builder.Services.AddScoped<IHubContext<MessageHub>>();

But it does not work.

Update:

private readonly UserManager<AppUser> _userManager;
private readonly SignInManager<AppUser> _signInManager;
private readonly IUserRepository _userRepository;
private readonly INotificationRepository _notificationRepository;
private readonly IHubContext _hubContext;
    
public HomeController(
    UserManager<AppUser> userManager,
    SignInManager<AppUser> signInManager,
    IUserRepository userRepository,
    INotificationRepository notificationRepository,
    IHubContext hubContext
)
{
    _userManager = userManager;
    _signInManager = signInManager;
    _userRepository = userRepository;
    _notificationRepository = notificationRepository;
    _hubContext = hubContext;
}