Crazy with callbacks

I'm going crazy,
I think I did everything correctly, because I took the code of another example of my project and everything works properly them.

Controller:

PHP Code:

public function title_check_exist($title) {
                $this->pages->title_check($title);
    }
    public function link_check_exist($link) {
                $this->pages->link_check($link);
    }
        public function create() {
                $rules = array(
                array(
                    'field'=>'title',
                    'label'=>'Titolo della pagina',
                    'rules'=>'alpha|required|min_length[3]|callback_title_check_exist'
                ),
                                array(
                    'field'=>'link',
                    'label'=>'Link della pagina',
                    'rules'=>'min_length[3]|required|callback_link_check_exist'
                ),
                                array(
                    'field'=>'message',
                    'label'=>'Testo della pagina',
                    'rules'=>'min_length[20]|required'
                )

            );
.... 


Model:

PHP Code:

public function title_check($title) {
        $db = $this->load->database('default', TRUE);
        $db->where('title',$title);
        $query = $db->get('pagine');
        if ($query->num_rows() > 0){
            return TRUE;
            $this->form_validation->set_message('title_check', 'Il titolo è già utilizzato.');
        }else{
            return FALSE;
        }
    }
    public function link_check($link) {
        $db = $this->load->database('default', TRUE);
        $db->where('link',$link);
        $query = $db->get('pagine');
        if ($query->num_rows() > 0){
            return TRUE;
            $this->form_validation->set_message('link_check', 'Il link è già utilizzato.');
        }else{
            return FALSE;
        }
    } 


When I insert a title or a link already exists in the database, it is not calculated but also created the page.

All other rules instead are read properly and when something deliberately wrong in the callback is signaled.

What is the error that I can not find?



Thanks for your continued support that you give me.

EDIT: I can try edit this part

PHP Code:

if ($query->num_rows() > 0){
            return TRUE;
            $this->form_validation->set_message('title_check', 'Il titolo è già utilizzato.');
        }else{
            return FALSE;
        } 


with this code:

PHP Code:

if ($title = 'title of page'){
            return TRUE;
            $this->form_validation->set_message('title_check', 'Il titolo è già utilizzato.');
        }else{
            return FALSE;
        } 


and the result it is the same.