Modifcare cod. Functie onchange nefunctionala

public function city() {
  $output = '<option value="">' . $this->language->get('text_select') . '</option>';
  $this->load->model('localisation/city');
  $results = $this->model_localisation_city->getCitiesByZoneId($this->request->get['zone_id']);
  foreach ($results as $result) {
   $output .= '<option value="' . $result['city_id'] . '"';
   if (isset($this->request->get['city_id']) && ($this->request->get['city_id'] == $result['city_id'])) {
$output .= ' selected="selected"';
   }
   $output .= '>' . $result['name'] . '</option>';
  }
  if (!$results) {
   $output = '<option value="0">' . $this->language->get('text_none') . '</option>';
  } else {
   $output .= '<option value="0">' . $this->language->get('text_none') . '</option>';
  }
  $this->response->setOutput($output);
}
public function coduri() {
  $json = array();
  $this->load->model('localisation/city');
  $coduri_info = $this->model_localisation_city->getCoduri($this->request->get['city_id']);
  if ($coduri_info) {
   $json = array(
'city_id'  => $coduri_info['city_id'],
'postcode' => $coduri_info['postcode'],
   );
  }
  $this->response->setOutput(json_encode($json));
}

<?php
class ModelLocalisationCity extends Model {
public function getCity($city_id) {
  $query = $this->db->query("SELECT * FROM " . DB_PREFIX . "city WHERE city_id = '" . (int)$city_id . "' AND status = '1'");

  return $query->row;
}

public function getCitiesByZoneId($zone_id) {
  $city_data = $this->cache->get('city.' . (int)$zone_id);

  if (!$city_data) {
   $query = $this->db->query("SELECT * FROM " . DB_PREFIX . "city WHERE zone_id = '" . (int)$zone_id . "' AND status = '1' ORDER BY name");

   $city_data = $query->rows;
  
   $this->cache->set('city.' . (int)$zone_id, $city_data);
  }

  return $city_data;
}
public function getCoduriByCityId($city_id) {
  $coduri_data = $this->cache->get('postcode.' . (int)$city_id);

  if (!$coduri_data) {
   $query = $this->db->query("SELECT * FROM " . DB_PREFIX . "postcode WHERE city_id = '" . (int)$city_id . "' AND status = '1' ORDER BY name");

   $coduri_data = $query->rows;
  
   $this->cache->set('postcode.' . (int)$city_id, $coduri_data);
  }

  return $coduri_data;
}
}

<div class="form-group required">
<label class="col-sm-2 control-label" for="input-zone"><?php echo $entry_zone; ?></label>
<div class="col-sm-10">
   <select name="zone_id" class="form-control" onchange="$('select[name=\'city\']').load('index.php?route=account/register/city&zone_id=' + this.value);">>
<option value=""><?php echo $text_select; ?></option>
<?php foreach ($zones as $zone) { ?>
<?php if ($zone['zone_id'] == $zone_id) { ?>
<option value="<?php echo $zone['zone_id']; ?>" selected="selected"><?php echo $zone['name']; ?></option>
<?php } else { ?>
<option value="<?php echo $zone['zone_id']; ?>"><?php echo $zone['name']; ?></option>
<?php } ?>
<?php } ?>
  </select>
  <?php if ($error_zone) { ?>
  <div class="text-danger"><?php echo $error_zone; ?></div>
  <?php } ?>
</div>
  </div>
  <div class="form-group required">
<label class="col-sm-2 control-label" for="input-city"><?php echo $entry_city; ?></label>
<div class="col-sm-10">
   <select name="city" id="input-city" class="form-control"  onchange="getCoduriP();">
  </select>
  <?php if ($error_city) { ?>
  <div class="text-danger"><?php echo $error_city; ?></div>
  <?php } ?>
</div>
  </div>

function getCoduriP() {
var orase = $('select[name=\'city\']').val();

$.ajax({
  url: 'index.php?route=account/register/city&city_id=' + orase,
  dataType: 'html',
  success: function (data) {
   $('#postcode').val(data);  
  }
});
}