Duplicate table created when adding IdentityUser as foreign key in ASP.NET Core 3.1

I am using PostgreSql as my DB. I am trying to add a foreign key to the user's table but instead of that a duplicate IdentityUser table is being created.

I have inherited IdentityDbContext<IdentityUser> for ApplicationDbContext whose code is:

public class ApplicationDbContext : IdentityDbContext<IdentityUser>
{
    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
        : base(options)
    {
    }

    protected override void OnModelCreating(ModelBuilder builder)
    {
        base.OnModelCreating(builder);
    }
}

This is able to create all the tables as:

I am trying to create a model where the user is the foreign key by doing:

public class AccountModel
{
    [Key]
    public string Id { get; set; } = Guid.NewGuid().ToString();

    public string AccountName { get; set; }

    public string AccountNumber { get; set; }

    public BankModel BankDetails { get; set; }

    public IdentityUser User { get; set; }
}

And it's DBContext is

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

    }

    public DbSet<AccountModel> Accounts { get; set; }
    public DbSet<BankModel> Banks { get; set; }
}

Looking at the post - https://stackoverflow.com/a/41275590/3782963, the accepted answer uses ApplicationUser which I believe is similar to IdentityUser, when I do the migrations, instead of adding an FK to AspNetUsers it creates a new table called IdentityUser and then an FK is added to this newly created table. Which looks like:

I am not sure what I am doing wrong. Help!

Update

I tried this code with Azure SQL Server too and it still gave me the same problem. Also, I added [ForeignKey("AspNetUser")]

public class AccountModel
{
    [Key]
    public string Id { get; set; } = Guid.NewGuid().ToString();

    public string AccountName { get; set; }

    public string AccountNumber { get; set; }

    public BankModel BankDetails { get; set; }

    [ForeignKey("AspNetUsers")]
    public IdentityUser User { get; set; }
}

I still get the same problem.

Update 2

The relationship is between two different contexts, i.e. ApplicationDbContext and AccountDbContext. Adding public DbSet<AccountModel> Accounts { get; set; } to ApplicationDbContext works fine and automatically adds an FK relationship.