I have a problem , my migration is not working, the version is added to the DB is 0 but I have configured 1 for version its not running my create table method

```
class Migration_Add_blog extends CI_Migration {

    public function up()
    {
        $this->dbforge->add_field(array(
            'blog_id' => array(
                'type' => 'INT',
                'constraint' => 5,
                'unsigned' => TRUE,
                'auto_increment' => TRUE
            ),
            'blog_title' => array(
                'type' => 'VARCHAR',
                'constraint' => '100',
            ),
            'blog_description' => array(
                'type' => 'TEXT',
                'constraint'=> '100'
            ),
        ));

        $this->dbforge->create_table('blog');
        $this->dbforge->add_key('id',TRUE);
    }

    public function down()
    {
        $this->dbforge->drop_table('blog');
    }
} 

```