Datagridview not showing data

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Microsoft.Office.Core;
using Microsoft.Office.Interop.Excel;
using System.Runtime.InteropServices;
using System.Reflection;
using System.Runtime.InteropServices.ComTypes;
using System.IO;
using System.Data.OleDb;
using System.Configuration;
using Excel = Microsoft.Office.Interop.Excel;

namespace WindowsFormsApplication1

{
    public partial class Form1 : Form
    {
        System.Data.DataTable ds = new System.Data.DataTable();
        OleDbDataAdapter adapter = new OleDbDataAdapter();
        DataGridView dataGridView1 = new DataGridView();
       
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {

            var datagrid = new Form3(); // Form 3 has the data grid view
            datagrid.Show();
                      
            string path = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
            path = Path.Combine(path, "Project Sunset_PLS Lien 2 Strats.xlsx");

            string Connectionstring = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + @";Extended Properties=""Excel 12.0

Macro;HDR=Yes;ImpoertMixedTypes=Text;TypeGuessRows=0""";
          
            OleDbConnection conn = new OleDbConnection(Connectionstring);
           
            string command_check = "Select * from [Strats$]";

            OleDbCommand cmd = new OleDbCommand(command_check, conn);

            try
            {
                conn.Open();
                ds.Clear();
                adapter.SelectCommand = cmd;
                adapter.Fill(ds);
                dataGridView1.AutoGenerateColumns = true;
                dataGridView1.DataSource = ds; // I can see data filled in ds, but datagrid is not showing anything
               
            }

            catch (Exception ex)
           {
               MessageBox.Show(ex.ToString());

          }
           finally
            {
                conn.Close();
            }
        }}}