Free Shipping Guarantee not working

[WessexWisdom]

Please would someone be kind enough to take a look at my shop?
I am in the UK. I have the free shipping guarantee in place, but a couple of days ago a customer in Texas with an order of around $40 was charged shipping, in other words, the free shipping guarantee didn't work.
I have since manually changed my delivery profiles to give free shipping over $35, but of course this won't work if a buyer purchases 2 items that are individually under $35, but come to more than $35 together. In that scenario they will still be charged shipping.
I cannot get customer support to understand my problem.
I'm not sure how the free shipping guarantee looks to a buyer browsing my shop, is there a banner or something, how's it looking please?

[CappuccinoLace · Accepted solution]

They may have been using an outdated version of the app that doesn't have the FSG.

I checked your shop, I see it (buy these items together and get free shipping; and a green banner in cart that tells you how much to add to get free shipping) and it's working fine.

[WessexWisdom]

Oh that is good news, thank you so much.