Is JSON response from WP-API Changed?

Hi, I am an IONIC 3 WordPress Blog app. I used

img src ="{{post.featured_image_urls.thumbnail}}"

to get image from JSON response. It was working fine till last night when I noticed that its throwing error. When I saw in JSON response there is no featured_image_urls option for all of my posts though all of them have media. I think they have changed and there is no option left for thumbnail, medium, large . Now my app is not working can someone please help me whats going on and how to fix it.

You have to ask Wordpress about that. The WP-API has nothing to do with Ionic.