Not updating ID - asp.net-core

Question

i am new to asp.net and i have a question. I have created a simple form fro sending sms, however my id always stays null. Can you please advise on what am i doing wrong? I used exactly the same form in my other page and it worked fine.
#model MessagingWebApplication.ViewModel.MessageViewModel
#{ ViewBag.Title = "New";
Layout = "~/Views/Shared/_Layout.cshtml";
}
<h2>New Sms</h2>
#using (Html.BeginForm("MessageStatus", "Message"))
{
#Html.ValidationSummary()
<div class="form-group">
#Html.LabelFor(m => m.Message.Reciever)
#Html.TextBoxFor(m => m.Message.Reciever, new { #class = "form-control" })
#Html.ValidationMessageFor(m => m.Message.Reciever)
</div>
<div class="form-group">
#Html.LabelFor(m => m.Message.Sender)
#Html.TextBoxFor(m => m.Message.Sender, new { #class = "form-control" })
#Html.ValidationMessageFor(m => m.Message.Sender)
</div>
<div class="form-group">
#Html.LabelFor(m => m.Message.Body)
#Html.TextBoxFor(m => m.Message.Body, new { #class = "form-control" })
#Html.ValidationMessageFor(m => m.Message.Body)
</div>
#Html.HiddenFor(m => m.Message.Id)
#Html.AntiForgeryToken()
<button type="submit" class="btn btn-primary">Send</button>
}
My model
public class Message
{
[Key]
public int Id { get; set; }
[Required]
public string Sender { get; set; }
[Required]
public string Reciever { get; set; }
[Required]
public string Body { get; set; }
}
Method used for sending
public ActionResult Send(Message message)
{
var viewModel = new MessageViewModel
{
Message = new Message()
};
_context.Add(message);
_context.SaveChanges();
_messageSender.Send(message);
return View("MessageStatus", viewModel);
}
here _context.SaveChanges(); i get SqlException: Cannot insert the value NULL into column 'Id', table 'MyDatabase.dbo.Messages'; column does not allow nulls. INSERT fails.

Answer 1

My issue was that i had failed when updating the database so i just followed this How to delete and recreate from scratch an existing EF Code First database