When you add or remove new language through Shopify admin, you have an option to sync it through app. Simply follow these steps to sync your store languages. App makes use of Shopify's "read_locales" scope to read your store languages.

  1. Go to "Design & Settings".
  2. Scroll down to "Advance configuration".
  3. Click on "Sync" next to listed languages.

Following screenshot shows exact location of this setting. Please sync only if you've made any changes in store languages, otherwise you don't need to touch this setting.