File Uploading Class doesn't allow xlsx extension.

[eluser]Unknown[/eluser]
When i try to upload a xlsx file i recived the error "The type file is not allowed". Is this a bug?


My code:

Code:

$config['upload_path'] = './assets/uploads/files/seguimiento/';
$config['allowed_types'] = 'xls|xlsx';
$config['max_size'] = '2048';
$config['file_name'] = 'FS_'.$usuario->username;
$this->load->library('upload', $config);
  
  
if ( ! $this->upload->do_upload("documento") )
{
      $datos['mensaje'] = $this->upload->display_errors();

}