Checking your site, I see that the order review on the Checkout page has an endless load, is this the issue you are referring to?
If so, I am seeing the following in the browser console of the checkout page:
It seems there is an AJAX error. Can you please take a look at the below support document, follow the suggestions provided there and see if any of these resolve the issue:
If the issue persists, let’s check if there are any errors in the WooCommerce logs. Can you please provide the following:
System Status Report: you can find this via WooCommerce → Status. Select Get system report and then Download for Support. This will download a TXT file that has the contents of the SSR which you can then share with us here.
Fatal Error Log: Share a copy of any fatal error log found under WooCommerce → Status → Logs.
