dotNET Scaffold won't generate code because of Entity with one-to-many relationship

Question

Just started using ASP.net, moved from JAVA. Trying to auto-generate controller for project. While I managed to do so in tutorial on official web-site, found a problem to make it work on my "test" project. Problem encountered when I put some collection inside Entity, without this collection it works fine.

The question is how to make it work? I assume that the problem is somewhere in connection between two DBs (which is one (User)-to-many(Links).

This is User model:

public class UserItem
{
    [Key]
    public long UserId { get; set; }

    [Required]
    [MinLength(3, ErrorMessage = "Min 3 char")]
    [MaxLength(20)]
    public string? Name { get; set; }

    [Required]
    [MinLength(6, ErrorMessage = "Min 6 char"), MaxLength(20)]
    public required string Password { get; set; } // todo: private set;

    // [ForeignKey("Links")]
    // [ConcurrencyCheck]
    public ICollection<LinkItem> Links { get; set; }

    public UserItem()
    {
        Links = new List<LinkItem>();
    }
}

This is Link model:

public class LinkItem
{
    [Key]
    public long UserId { get; set; }
    [ForeignKey("UserId")]
    public UserItem? UserItem { get; set; }
    public string? Link { get; set; }
}

This is DbContext:

public class UserLinksDb : DbContext
{
    public UserLinksDb(DbContextOptions<UserLinksDb> options) : base(options) { }

    public DbSet<UserItem> UserItems { get; set; } = null!;
    public DbSet<LinkItem> LinkItems { get; set; } = null!;

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<LinkItem>().HasKey(k => k.UserId);
        modelBuilder.Entity<LinkItem>( e => 
        {
            e.HasKey(k => k.UserId);
            e.HasOne(k => k.UserItem)
            .WithMany(k => k.Links)
            .HasForeignKey(k => k.UserId)
            .OnDelete(DeleteBehavior.ClientSetNull);
        });
    }
}

This is how I connect to in-memory DB :

builder.Services.AddDbContext<UserLinksDb>(option => option.UseInMemoryDatabase("LinksList"));

And this is how I try to generate controller:

dotnet aspnet-codegenerator controller -name LinksController -async -api -m UserItem -dc UserLinksDb -outDir Controllers

When I try to execute code-generator command in terminal, I get this error: Could not get the reflection type for DbContext : UserLinksDb