Datagridview combobox selected item to sql database

It's my code for datagridviewcombobox convert to string 

its workin but when i go to my database table in SQL

"DataGridViewComboBoxCell { ColumnIndex=0, RowIndex=1 }" in the cells.
 SqlConnection con = new SqlConnection("Data Source=DESKTOP-7SLRDRG\\MSSQLSERVER01;Initial Catalog=ALBAYRAK;Integrated Security=True");
                con.Open();
                string kaydet = "INSERT INTO SİPARİŞDETAY(PROJEKODU,ANAGRUPKODU,GRUPKODU,ÜRÜNKODU,ALTPARÇAKODU,MİKTAR,TÜR) VALUES (@PK,@AK,@GK,@ÜK,@ALTK,@miktar,@tur)";
                SqlCommand cmd = new SqlCommand(kaydet, con);


            int n = dataGridView1.Rows.Add();

         

cmd.Parameters.AddWithValue("PK", Convert.ToString(dataGridView1.Rows[1].Cells[0]));
            cmd.Parameters.AddWithValue("@AK",dataGridView1.Rows[1].Cells[1].ToString());
            cmd.Parameters.AddWithValue("@GK",dataGridView1.Rows[1].Cells[2].ToString());
            cmd.Parameters.AddWithValue("@ÜK",dataGridView1.Rows[1].Cells[3].ToString());
            cmd.Parameters.AddWithValue("@ALTK",dataGridView1.Rows[1].Cells[4].ToString());
            cmd.Parameters.AddWithValue("@miktar",dataGridView1.Rows[1].Cells[5].Value);
            cmd.Parameters.AddWithValue("@tur",dataGridView1.Rows[1].Cells[6].ToString());

            dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect;
            cmd.ExecuteNonQuery();

                con.Close();

                MessageBox.Show("siparişiniz oluşturuldu!");

how can i get the datagridview selected item to my database?

thanks in advance