diff --git a/src/langs/lang.ts b/src/langs/lang.ts
index 06f94db..1e215f0 100644
--- a/src/langs/lang.ts
+++ b/src/langs/lang.ts
@@ -2,48 +2,114 @@ import path from 'path';
 import fs from 'fs';
 import { NextFunction, Request, Response } from 'express';
 
+// interface LanguageValue {
+//     success_insert?: string;
+//     success_update?: string;
+//     success_delete?: string;
+//     success_restore?: string;
+//     success_view?: string;
+//     success?: string;
+//     success_valid_otp?: string;
+
+//     failed?: string;
+//     failed_access?: string;
+//     failed_access_otp?: string;
+//     failed_expired_otp?: string;
+//     failed_access_pin?: string;
+//     failed_try_pin?: string;
+//     failed_insert?: string;
+//     failed_update?: string;
+//     failed_delete?: string;
+//     failed_restore?: string;
+//     failed_save?: string;
+//     failed_view?: string;
+//     failed_empty?: string;
+//     failed_data?: string;
+//     failed_duplicate?: string;
+//     failed_not_found?: string;
+//     failed_limit_otp?: string;
+//     failed_limit_link_code?: string;
+//     failed_expired_token?: string;
+//     failed_token?: string;
+//     failed_add_point?: string;
+
+//     //login
+//     success_login?: string;
+//     failed_password?: string;
+// }
+
+// export class Language {
+//     static lang_init: LanguageValue = {};
+//     static lang: LanguageValue = {};
+
+//     static setup() {
+//         const fileLang: any = fs.readFileSync(
+//             path.join(__dirname, '../langs/json/en.json')
+//         );
+//         Language.lang_init['en'] = JSON.parse(fileLang.toString('utf8'));
+//     }
+
+//     static apply = (req: Request, res: Response, next: NextFunction) => {
+//         const acceptLanguageHeader = req.get('Accept-Language') as string | null;
+//         if (!acceptLanguageHeader) {
+//             //default
+//             req.params.language = 'en';
+//         } else {
+//             req.params.language = acceptLanguageHeader.substring(0, 2).toLowerCase();
+//         }
+
+//         Language.lang = Language.lang_init[req.params.language] ? Language.lang_init[req.params.language] : Language.lang_init['en'];
+
+//         return next();
+//     }
+// }
+
 interface LanguageValue {
-    success_insert?: string;
-    success_update?: string;
-    success_delete?: string;
-    success_restore?: string;
-    success_view?: string;
-    success?: string;
-    success_valid_otp?: string;
+    success_insert: string;
+    success_update: string;
+    success_delete: string;
+    success_restore: string;
+    success_view: string;
+    success: string;
+    success_valid_otp: string;
 
-    failed?: string;
-    failed_access?: string;
-    failed_access_otp?: string;
-    failed_expired_otp?: string;
-    failed_access_pin?: string;
-    failed_try_pin?: string;
-    failed_insert?: string;
-    failed_update?: string;
-    failed_delete?: string;
-    failed_restore?: string;
-    failed_save?: string;
-    failed_view?: string;
-    failed_empty?: string;
-    failed_data?: string;
-    failed_duplicate?: string;
-    failed_not_found?: string;
-    failed_limit_otp?: string;
-    failed_limit_link_code?: string;
-    failed_expired_token?: string;
-    failed_token?: string;
-    failed_add_point?: string;
+    failed: string;
+    failed_access: string;
+    failed_access_otp: string;
+    failed_expired_otp: string;
+    failed_access_pin: string;
+    failed_try_pin: string;
+    failed_insert: string;
+    failed_update: string;
+    failed_delete: string;
+    failed_restore: string;
+    failed_save: string;
+    failed_view: string;
+    failed_empty: string;
+    failed_data: string;
+    failed_duplicate: string;
+    failed_not_found: string;
+    failed_limit_otp: string;
+    failed_limit_link_code: string;
+    failed_expired_token: string;
+    failed_token: string;
+    failed_add_point: string;
 
-    //login
-    success_login?: string;
-    failed_password?: string;
+    success_login: string;
+    failed_password: string;
+}
+
+// Tambah index signature agar bisa akses dengan ['en']
+interface LanguageStore {
+    [key: string]: LanguageValue;
 }
 
 export class Language {
-    static lang_init: LanguageValue = {};
-    static lang: LanguageValue = {};
+    static lang_init: LanguageStore = {};
+    static lang: LanguageValue = {} as LanguageValue;
 
     static setup() {
-        const fileLang: any = fs.readFileSync(
+        const fileLang = fs.readFileSync(
             path.join(__dirname, '../langs/json/en.json')
         );
         Language.lang_init['en'] = JSON.parse(fileLang.toString('utf8'));
@@ -52,13 +118,13 @@ export class Language {
     static apply = (req: Request, res: Response, next: NextFunction) => {
         const acceptLanguageHeader = req.get('Accept-Language') as string | null;
         if (!acceptLanguageHeader) {
-            //default
             req.params.language = 'en';
         } else {
             req.params.language = acceptLanguageHeader.substring(0, 2).toLowerCase();
         }
 
-        Language.lang = Language.lang_init[req.params.language] ? Language.lang_init[req.params.language] : Language.lang_init['en'];
+        Language.lang = Language.lang_init[req.params.language]
+            ?? Language.lang_init['en'];
 
         return next();
     }