Foreign key reference to IdentityUser Table shows Null after Inserting in ASP.Net MVC

Referencing Foreign key to IdentityUser. Table with FK Shows Null after Inserting Data.

I'm quite new to ASP.NET MVC. What I've made is a Register and Login from the Scaffolding Views.

Another table I've made is "Feedback" and it has a foreign key "UserId" referencing to ASP.Net Identity User which is the "Id" field. Once I've done creating a Create() View for the feedback, it has been successfully saving the 2 fields that I want but not the UserId, which just shows null.

How do I even work with this to reference the Id of the current user to the feedback table.

Here are my code

So my main question is: How, and what can I do to automatically insert the UserId ForeignKey to my Feedback table, because what I want to happen is whenever a logged in user is posting a feedback, I also want to link their IdentityUser Id to my Feedback table in the form of a foreignkey UserId.

Feedback Model

public class Feedback
{
    [Key]
    public int FeedbackId { get; set; }
 
    [Required(ErrorMessage = "Subject Required.")]
    public string Subject { get; set; }
 
    [Required]
    [DataType(DataType.MultilineText)]
    public string Text { get; set; }
 
    public string UserId { get; set; }
 
    [ForeignKey("UserId")]
    public virtual ApplicationUser User { get; set; }
 
    public ICollection<Feedback> Feedbacks { get; set; }
}

FeedbackController for creating a Feedback

[HttpPost]
public IActionResult Create(Feedback record)
{
    var item = new Feedback()
    {
        Subject = record.Subject,
        Text = record.Text,
    };
 
    _context.Feedbacks.Add(item);
    _context.SaveChanges();
 
    return RedirectToAction("Index");
}