Object reference not set to an instance of the object

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
        {
            GridViewRow row = (GridViewRow)GridView1.Rows[e.RowIndex];
            Label lblID = (Label)row.FindControl("lblID");
            
            TextBox textName = (TextBox)row.FindControl("txtName");
            TextBox textDesc = (TextBox)row.FindControl("txtDesc");
            TextBox textImage = (TextBox)row.FindControl("txtImage");
            TextBox textActive = (TextBox)row.FindControl("txtActive");
            TextBox textCreatedBy = (TextBox)row.FindControl("txtCreatedBy");
            TextBox textCreatedDate = (TextBox)row.FindControl("txtCreatedDate");
            GridView1.EditIndex = -1;
            conn.Open();
            
            
            SqlCommand cmd = new SqlCommand("UPDATE tbl_SqlImage set Name=" + textName.Text + " , Description='" + textDesc.Text + " , Image='" + textImage.Text + " , Active='" + textActive.Text + " , CreatedBy='" + textCreatedBy.Text + " , CreatedDate='" +textCreatedDate.Text + "' where ID=" + lblID.Text + "", conn);
            
            
            cmd.ExecuteNonQuery();
            conn.Close();
            bind();
            //GridView1.DataBind();
            
        }