Merubah URL kategori swarakaliba CI eror 404 page not found

Assalamualaikum Warahmatullahi Wabarakatuh...
mas roby dan para masta mohon bantuannya..
 
saya mau tanya kenapa saat saya rubah url kategori yang awal kategori/detail saya rubah jadi kategoriberita eror 404 page not found
 
saya sdh rubah di file controller kategori.php  tp kenapa eror 404 page not found
 
<?php
 
defined('BASEPATH') OR exit('No direct script access allowed');
class Kategori extends CI_Controller {
	public function detail(){
		$query = $this->model_utama->view_where('kategoriberita',array('kategori_seo' => $this->uri->segment(2)));
		if ($query->num_rows()<=0){
			redirect('main');
		}else{
			$row = $query->row_array();
			$jumlah= $this->model_utama->view_where('berita',array('id_kategori' => $row['id_kategori']))->num_rows();
			$config['base_url'] = base_url().'kategoriberita'.$this->uri->segment(2);
			$config['total_rows'] = $jumlah;
			$config['per_page'] = 10; 	
			if ($this->uri->segment('4')==''){
				$dari = 0;
			}else{
				$dari = $this->uri->segment('4');
			}
			$data['title'] = "Berita Kategori $row[nama_kategori]";
			$data['description'] = description();
			$data['keywords'] = keywords();
			$data['rows'] = $row;
			if (is_numeric($dari)) {
				$data['beritakategori'] = $this->model_utama->view_join_two('berita','users','kategoriberita','username','id_kategori',array('berita.id_kategori' => $row['id_kategori']),'id_berita','DESC',$dari,$config['per_page']);
			}else{
				redirect('main');
			}
			$this->pagination->initialize($config);
			$this->template->load(template().'/template',template().'/detailkategori',$data);
		}
	}
}
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