代码点火器验证错误，字段为“必需”

我对验证表单有问题。如果我输入"必需"，它不起作用，例如：

控制器：

public function updateBenefit(){
    $result = array();
    $this->load->helper(array('form', 'url'));
    $this->load->library('form_validation');
    $this->form_validation->set_rules('beneficio', 'Nombre del Beneficio', 'required|alpha');
    $this->form_validation->set_rules('info', 'Info', 'alpha');
    $this->form_validation->set_rules('descrip', 'Descripción', 'alpha');
    $this->form_validation->set_rules('orden', 'Orden', 'integer');
    // $this->form_validation->set_rules('fecha', 'Fecha', 'date_valid');
    $this->form_validation->set_message('required', 'El campo %s es requerido');
    if ($this->form_validation->run() == TRUE){
        if (isset($_POST['id'])){
            $idb = $_POST['id'];
            $benefit = BeneficiosManager::getInstance()->getHome($idb);
            $result['message'] = "Se ha modificado el Beneficio con éxito"; 
        } else{
            $benefit = BeneficiosManager::getInstance()->create();
            $result['message'] = "Se ha cargado el Beneficio con éxito"; 
        }
        $benefit->nombre = ucfirst(strtolower($_POST['beneficio']));
        $benefit->content = ucfirst(strtolower($_POST['descrip']));
        $benefit->intro = ucfirst(strtolower($_POST['info']));
        $benefit->active = $_POST['optionsRadios2'];
        $benefit->orden = $_POST['orden'];
        // $benefit->date = $_POST['fecha'];
        BeneficiosManager::getInstance()->save($benefit);
        }else{
            //no se validaron los datos ingresados
            $result['message'] = "Error validación";
        }
        echo json_encode($result);
}

视图：

    {extends file='admin/base/base.tpl'}
{block name='content'}
<h3>Cargar Beneficio </h3>
</br>
<form action="{site_url()}admin/updateBenefit" class="form-horizontal" method="post" id="" enctype="multipart/form-data">
   <div class="control-group">
      <label class="control-label">Beneficio</label>
      <div class="controls">
         <input type="text" name="beneficio" value="" class="m-wrap medium" />
         <span class="help-inline">Nombre del Beneficio</span>
      </div>
   </div>
   <div class="control-group">
      <label class="control-label">Info</label>
      <div class="controls">
         <textarea name="info" class="medium m-wrap" rows="3"></textarea>
         <span class="help-inline">Información Clave</span>
      </div>
   </div>
   <div class="control-group">
      <label class="control-label">Descripción</label>
      <div class="controls">
         <textarea name="descrip" class="large m-wrap" rows="3"></textarea>
         <span class="help-inline">Descripción del Beneficio</span>
      </div>
   </div>
   <div class="control-group">
      <label class="control-label">Activo</label>
      <div class="controls">
            <label class="radio line">
               <input type="radio" name="optionsRadios2" value="1"/>Si</input>
            </label>
            <label class="radio line">   
               <input type="radio" name="optionsRadios2" value="0"/>No</input>
            </label>
         <span class="help-inline">Ofrecer Beneficio</span>
      </div>
   </div>
   <div class="control-group">
      <label class="control-label">Orden</label>
      <div class="controls">
         <input type="text" name="orden" value="" class="m-wrap small" />
         <span class="help-inline">Prioridad del Beneficio</span>
      </div>
   </div>
   <div class="control-group">
      <label class="control-label">Fecha</label>
      <div class="controls">
         <input type="text" name="fecha" value="{$smarty.now|date_format}" class="m-wrap medium" />
         <span class="help-inline"></span>
      </div>
   </div>   
   <div class="form-actions">
      <button type="submit" class="btn blue"><i class="icon-ok"></i> Guardar</button>
      <button type="button" class="btn">Cancelar</button>
   </div>
</form>
{/block}

可能有什么问题？

如果我删除"必填"字段，表单将验证...但如果我说的话，它不会...我不知道还能尝试什么，不明白为什么会这样

代码现在可以工作了，这要归功于纠正我的@Jonathan，而且我在尝试这种方法时也犯了一个输入错误。我试图在同一字段中放置两个词（即：bon vivir）;所以正确的输入是：邦维维尔。