Free shipping missing

We’re running the latest version of WC, WP and using the popular Flatsome theme. We have a development (private) site and a public site, which utilises Cloudflare. We’ve got a strange issue where our free shipping option won’t display on the live site, but works fine on the test site. All the settings are the same and triple checked. We have set the base location to manually be the UK and the free shipping is for UK people only. We’ve tried putting in full addresses, tried private browser mode, etc. etc. – but it works fine on the dev site and not fine on www. Therefore the only things that are not constant between the two is the database (as the live one is more regularly changed due to orders, new products) and the fact it’s behind Cloudflare.

Any ideas?

https://ww.wp.xz.cn/plugins/woocommerce/