Ben here with the Webflow Customer Support Team!
So sorry for any delay here. I did some checking on my end and I am seeing the shipping method pop up:
I did see an issue with your checkout page though. It looks like you have the body set to
overflow: hidden. This keeps people from scrolling down which may be why they can’t see the shipping options.
If you change that to
overflow: visible they can scroll and should be able to choose a shipping method. Here’s a quick gif to show you how to fix it:
Let me know if you have any other questions, and I’ll be happy to assist you further!