Hi there!
If the customer truly selected Stripe at Checkout, it is very strange that it would process the order as “Direct Bank Transfer” instead.
I took a look at your site, and saw a bit of strange behavior: after trying to add a product to Cart, I clicked the “View cart” button but it was showing the Cart as empty. This type of issue is most often caused by caching on the site.
Please make sure your Cart, Checkout, and My Account pages are all excluded from any caching plugins you have installed on the site. Also, please reach out to your hosting company to make sure those pages are excluded from caching on the server itself as well.
After going back to the product and trying to add it to Cart again, it said it couldn’t add it to Cart because there was only 1 in stock (and it was already in Cart). I went back to the Cart page again and saw the product there, then proceeded to the Checkout page where I saw that “Direct Bank Transfer” is the default payment option, with Stripe as one of the other options.
It’s possible something relating to Caching may have caused the strange behavior for the Checkout with your other customer as well (not just what I saw on the Cart). Once you have made sure those pages are not being cached, please try placing test orders on the site with Stripe and see if they work as expected.
If you are still having trouble, please share a copy of your site’s System Status. You can find it via WooCommerce > Status. Select “Get system report” and then “Copy for support”. Once you’ve done that, you can paste it here in your reply. Please note that since this is a public forum, you may want to remove any sensitive information that you don’t want shared publicly.
Please let me know how that goes, or if you have any questions!