The property or indexer cannot be used in this context because the set accessor is inaccessible Asp.net C#

The error appeared after i fixed another error in another Page

Here is the Code

using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Webshop3.Models;

namespace Webshop3.Pages.Management
{
    public partial class ManageProducts : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                GetImages();

                if (!String.IsNullOrWhiteSpace(Request.QueryString["id"]))
                {
                    int id = Convert.ToInt32(Request.QueryString["id"]);
                    FillPage(id);
                }


            }


        }

        protected void btnSubmit_Click(object sender, EventArgs e)
        {
            ProductModel productModel = new ProductModel();
            Product product = CreateProduct();

            //testojme nese url ka parameter id
            if (!String.IsNullOrWhiteSpace(Request.QueryString["id"]))
            {

                // ID existon -> update rreshtin ekzistes
                int id = Convert.ToInt32(Request.QueryString["id"]);
                lblResult.Text = productModel.UpdateProduct(id, product);
            }

            else
            {
                // nese nuk ekziston ID , krijo rresht te ri
                lblResult.Text = productModel.InsertProduct(product);
            }






        }

        private void FillPage(int id)
        {
            //Marim produktin e selektuar nga databaza
            ProductModel productModel = new ProductModel();
            var product = productModel.GetProduct(id);


            //Mbushim textboxat
            txtDescription.Text = product.Description;
            txtName.Text = product.Name;
            txtPrice.Text = product.Price.ToString();


            ddlImage.SelectedValue = product.Image;
            ddlType.SelectedValue = product.TypeId.ToString();




        }

        private void GetImages()
        {
            try
            {
                // Marim Images te Dropdown
                string[] images = Directory.GetFiles(Server.MapPath("~/Images/Products/"));

                // Vendoj FileName ne arraylist

                ArrayList imageList = new ArrayList();
                foreach (string image in images)
                {
                    string imageName = image.Substring(image.LastIndexOf(@"\", StringComparison.Ordinal) + 1);
                    imageList.Add(imageName);
                }

                ddlImage.DataSource = imageList;
                ddlImage.AppendDataBoundItems = true;
                ddlImage.DataBind();

            }

            catch (Exception e)
            {
                lblResult.Text = e.ToString();
            }

        }

        private Product CreateProduct()
        {
            Product product = new Product();
            product.Name = txtName.Text;
            product.Price = Convert.ToInt32(txtPrice.Text);
            product.TypeId = Convert.ToInt32(ddlType.SelectedValue);
            product.Description = txtDescription.Text;

            product.Image = ddlImage.SelectedValue;

            return product;

        }


    }
}

I was following a tutorial on youtube and i did the exact same thing as him , everything worked well until i arrived at this moment

Here is The Compiler Error

Compiler Error

Here is the Table in the Database

Table in Database