Angular translate static files loader not working in Android

My app is using Angular Translate. It works very fine on the web using ionic serve.
But when I build it to Android, the json file isn’t loaded and no error is shown. I use chrome inspector to check the network requests.
I have checked an earlier question, my prefix doesn’t have / at the beginning.

              prefix: 'js/locales/',
              suffix: '.json'

My directory structure


I am very frustrated now :frowning: