Error Message With Credit/Debit Card Button

I am having a problem with the “Credit or Debit Cards” button behaviour on a site I am building.

I have opted not to show the PayPal button on either the product pages or the cart page, as I only want it to show at checkout.

In the Regular Checkout Button Settings, I have kept the “Hide Funding Method” box blank, as I want to show the “Credit Or Debit Cards” Button at checkout.

The buttons display correctly at checkout, but when I click on the “Credit Or Debit Card” button, I get the error message “Something went wrong. We’ll take you back to checkout so you can try again”.

When I click on the “Try Again” button I now get the correct result, as it displays a popup that lets me enter my credit card details.

My question is why is the error message being displayed, and how do I fix it?

Strangely, the error only seems to happen on desktop, and not on mobile.

If it is relevant, I have the latest version of WordPress installed, and my theme and all plugins (including Woocommerce) are all up to date.

I have attached a link to a typical product page on the site, and I would be grateful for any suggestions.

PS: When it does work on desk top, the popup which the Credit Or Debit Card button triggers is quite small. Is there any way to enlarge this?

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