Model basic CRUD methods and other queries on other tables using $this->db->table()

When you use  table('table_name'), you are using a new Query Builder instance directly.
You are not using the Model.

Yes, I know this, this is the problem right here, because if I don't use table() of the query builder, the query fails?

The Model has its own table set, and the query in question should use that table "sottoeventi".

Code:

protected $table = 'sottoeventi';

In the specific case I first run other queries with the query builder, use different tables than the model one, then use table('other_table').

PHP Code:

$this->db->table('sottoeventi_personale')->where('id_sottoevento', (int)$id_sottoevento)->delete();

// Log
$basic_stuff_model->save_log('Delete giornate sottoevento', $this->db->getLastQuery());

$this->where('id', (int)$id_sottoevento)
        ->update(
            [
                'data_inizio' => '0000-00-00',
                'data_fine'   => '0000-00-00'
            ]
        ); 


The update query returns the error "There is no data to update", while you expect it to update the "sottoeventi" table, which is the Model