i18next: In Production, translation is not working

Localhost translation works completely fine, but when deployed in production, text is not being translated. Please help am using i18next-express-middleware.

i18next
  .use(Backend)
  .use(i18nextMiddleware.LanguageDetector)
  .init({
    backend: {
      loadPath: path.join(__dirname + '/locales/{{lng}}.json'),
      addPath: __dirname + '/locales/{{lng}}.missing.json'
    },
    detection: {
      order: ['path','cookie','querystring'],
      caches: ['cookie']
    },
    fallbackLng: 'en',
    preload: ['en', 'zh-hans'],
    saveMissing: true
  });