Ghost API - Posts not appearing on local development site

I have my main website pulling in the latest 5 posts from my Ghost blog which is on a sub-domain.

It all works perfectly on the live site.

The problem is that I can’t test any changes on my local development site because nothing loads. I just can’t get it to display anything at all. If I push changes to production live site, all it good.

What do I need to change here to get it to work?