没有任何东西被写入数据库

我是 ASP.Net 的初学者。我正在使用实体框架数据库优先方法。我需要将数据存储在我的音乐数据库中，在名为LogTable的表中。我尝试了很多方法。什么都没用。最后我尝试了这个：

在登录中.aspx

using System;
using System.Configuration;
using System.Web;
using System.Web.UI;
using Microsoft.AspNet.Identity;
using Microsoft.AspNet.Identity.EntityFramework;
using Microsoft.Owin.Security;
using MusicShop.Models;
namespace MusicShop.Pages.Accounts
{
public partial class Login : Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
    }
    protected void btnLogin_OnClick(object sender, EventArgs e)
    {
        var userStore = new UserStore<IdentityUser>();
        userStore.Context.Database.Connection.ConnectionString =
            ConfigurationManager.ConnectionStrings["MUSICConnectionString"].ConnectionString;
        var manager = new UserManager<IdentityUser>(userStore);
        var user = manager.Find(txtUserName.Text, txtPassword.Text);

        if (user != null)
        {
            InsertUserLog();
            var authenticationManager = HttpContext.Current.GetOwinContext().Authentication;
            var userIdentity = manager.CreateIdentity(user, DefaultAuthenticationTypes.ApplicationCookie);
            authenticationManager.SignIn(new AuthenticationProperties
            {
                IsPersistent = false
            }, userIdentity);

            Response.Redirect("~/Index.aspx");
        }
        else
        {
            litStatus.Text = "Invalid username or password";
        }
    }
    private void InsertUserLog()
    {
            LogModel model = new LogModel(); //Add a new model
            var logtable = new LogTable
            {
                IP = Request.ServerVariables["REMOTE_ADDR"].ToString(),
                //You could set a break point to check the value.
                AGENT = Request.ServerVariables["http_user_agent"].ToString(),
                REQM = Request.ServerVariables["request_method"].ToString(),
                SERVER = Request.ServerVariables["server_name"].ToString(),
                PORT = Request.ServerVariables["server_port"].ToString(),
                SW = Request.ServerVariables["server_software"].ToString(),
                DNS = Request.ServerVariables["REMOTE_HOST"].ToString()
            };
            //set value
            var error = model.InsertLog(logtable);
            if (error != null) Response.Write(error);
    }
}
}

在日志模型中.cs

public string InsertLog(LogTable logTable)
{
    try
    {
        MUSICEntities db = new MUSICEntities();
        db.LogTables.Add(logTable);
        db.SaveChanges();
        return null;
    }
    catch (Exception e)
    {
        return "Error:" + e;
    }
}

没有错误。但是没有任何东西添加到数据库中。谁能指导我？请原谅我，如果这是一个愚蠢的错误。

var error = model.InsertLog(logtable);
if(error != null) Response.Write(error);