i have a register page on my website I am creating and it saves the data entered by the user into a database however when I click the register button i am coming across the following error:

Insert Error:CREATE DATABASE permission denied in database 'master'.
Cannot attach the file 'C:\Users\MyName\Documents\MyName\Docs\Project\SJ\App_Data\SJ-Database.mdf' as database 'SJ-Database'.

These are my connection strings:

<connectionStrings>
    <add name="ApplicationServices" connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\aspnetdb.mdf;User Instance=true" providerName="System.Data.SqlClient"/>

    <add name="MyConsString" connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|SJ-Database.mdf;
                             Initial Catalog=SJ-Database;
                             Integrated Security=SSPI;"
                             providerName="System.Data.SqlClient" />
  </connectionStrings>

Register page code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;



public partial class About : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }

    public string GetConnectionString()
    {
        //sets the connection string from your web config file "ConnString" is the name of your Connection String
        return System.Configuration.ConfigurationManager.ConnectionStrings["MyConsString"].ConnectionString;
    }

    private void ExecuteInsert(string name, string gender, string age, string address, string email)
    {
        SqlConnection conn = new SqlConnection(GetConnectionString());
        string sql = "INSERT INTO Register (Name, Gender, Age, Address, Email) VALUES "
                    + " (@Name,@Gender,@Age,@Address,@Email)";

        try
        {
            conn.Open();
            SqlCommand cmd = new SqlCommand(sql, conn);
            SqlParameter[] param = new SqlParameter[6];
            //param[0] = new SqlParameter("@id", SqlDbType.Int, 20);
            param[0] = new SqlParameter("@Name", SqlDbType.VarChar, 50);
            param[1] = new SqlParameter("@Gender", SqlDbType.Char, 10);
            param[2] = new SqlParameter("@Age", SqlDbType.Int, 100);
            param[3] = new SqlParameter("@Address", SqlDbType.VarChar, 50);
            param[4] = new SqlParameter("@Email", SqlDbType.VarChar, 50);


            param[0].Value = name;
            param[1].Value = gender;
            param[2].Value = age;
            param[3].Value = address;
            param[4].Value = email;


            for (int i = 0; i < param.Length; i++)
            {
                cmd.Parameters.Add(param[i]);
            }

            cmd.CommandType = CommandType.Text;
            cmd.ExecuteNonQuery();
        }
        catch (System.Data.SqlClient.SqlException ex)
        {
            string msg = "Insert Error:";
            msg += ex.Message;
            throw new Exception(msg);
        }
        finally
        {
            conn.Close();
        }
    }
    protected void cmdRegister_Click(object sender, EventArgs e)
    {
        if (txtRegEmail.Text == txtRegEmailCon.Text)
        {
            //call the method to execute insert to the database
            ExecuteInsert(txtRegName.Text,
                          txtRegAge.Text,
                          ddlRegGender.SelectedItem.Text,
                          txtRegAddress.Text, txtRegEmail.Text);
            Response.Write("Record was successfully added!");
            ClearControls(Page);
        }
        else
        {
            Response.Write("Email did not match");
            txtRegEmail.Focus();
        }
    }
    public static void ClearControls(Control Parent)
    {

        if (Parent is TextBox)
        { (Parent as TextBox).Text = string.Empty; }
        else
        {
            foreach (Control c in Parent.Controls)
                ClearControls(c);
        }
    }

}