Undefined property: CI_Input::$post

[eluser]joe_h[/eluser]
Hi I try to insert data through a controller that calls a function of the model and gives me the following error:

A PHP Error was encountered
Severity: Notice
Message: Undefined property: CI_Input::$post
Filename: ......php
Line Number: ....


Code that is in the function of this model is:

Code:

$this->provincia = $this->input->post['provincia'];
        if($this->provincia){
            $data = array(
                'provincia' => $this->provincia
            );
            $query = $this->db->insert('provincias', $data);

Any idea???