I cannot add the orders to the database - asp.net-core-mvc

Question

I am building an e-store with ASP.NET Core. I've created CRUD operations to add my products and save it to the database, it is working fine. Then I wanted to save the orders from the customers to my database, sadly I couldn't manage to do so.
When I click a button, it saves the order to the database and sends the customer to the thank you page.
Can you please check my code and tell me where am going wrong.
This is my OrderController:
[HttpPost]
public async Task<IActionResult> PlaceOrder([FromBody] Order model)
{
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
var order = new Order
{
OrderDate = DateTime.Now,
Name = model.Name,
Address = model.Address,
Email = model.Email,
PhoneNo = model.PhoneNo
};
var orderDetails = new List<OrderDetails>();
foreach (var item in model.OrderDetails)
{
orderDetails.Add(new OrderDetails
{
ProductId = item.ProductId,
// Quantity = item.Quantity,
// Price = item.Price,
Order = order
});
}
using (var context = new AppDbContext(_dbContextOptions))
{
context.Order.Add(order);
context.OrderDetails.AddRange(orderDetails);
await context.SaveChangesAsync();
}
// returns a HTTP 200 OK response to the client indicating that the operation was successful.
return Ok();
}
and this is the button from my view:
<p>
<a asp-controller="Order" asp-action="PlaceOrder" class="btn btn-primary addToCart">Place my order</a>
</p>
Order class:
public class Order
{
public Order()
{
OrderDetails = new List<OrderDetails>();
}
public int Id { get; set; }
[Display(Name = "Order No")]
public string OrderNo { get; set; }
[Required]
public string Name { get; set; }
[Required]
[Display(Name = "Phone Number")]
public string PhoneNo { get; set; }
[Required]
[EmailAddress]
public string Email { get; set; }
[Required]
public string Address { get; set; }
[Display(Name = "Today's Date")]
public DateTime OrderDate { get; set; }
public virtual List<OrderDetails> OrderDetails { get; set; }
}
Order details class
public class OrderDetails
{
public int Id { get; set; }
[Display(Name = "Order")]
public int OrderId { get; set; }
[Display(Name = "Product")]
public int ProductId { get; set; }
[ForeignKey("OrderId")]
public Order Order { get; set; }
[ForeignKey("PorductId")]
public Product Product { get; set; }
}