Free Shipping not triggering based on price of items

Hello.

I am working on a site for a client where we had previously set up free shipping to automatically trigger when the customer is from Australia and they have shopped over $150 worth of products. However, while testing, we found that free shipping is not triggering even when both of those two requirements are met. It used to work fine just a few days ago but suddenly after my client updated WordPress and/or a few plugins (that they don’t remember) it’s not working anymore.

The site is at http://stella-phoenix.com/

We are using the latest version of WordPress and all plugins currently.

Thanks in advance.

The page I need help with: [log in to see the link]