What's Broken?

[eluser]Bionicjoe[/eluser]
I changed something awhile back & I guess I didn't test it. Now I can't fix whatever I changed?

Trying to insert a record.
I get error

Message: Undefined index: addupdate
Filename: controllers/outage.php

NOTE: If I uncomment the redirect I'll see the error & the page redirects quickly with the update inserted into the DB. But why the error?

Code:

function addupdate() {
      //Submit an update to the 'UPDATES' table.
      $id = $this->uri->segment(3);
      $this->load->model('outage_model','',TRUE);
      $this->outage_model->addupdate($_POST['addupdate'], $_POST);
      $link = array('outage/editoutage', $_POST['outageid']);
    //redirect($link,'refresh');
  }

Model

Code:

function addupdate($id, $data)
    // Update one outage record
    {
      $this->db->where('outageid', $id);
      $this->db->insert('updates', $data);
    }