PayPal Plugin not working on iPhone?

Question

PayPal

Good afternoon, there is a site https://www.karenbarbe.com where on the product page, when you click on the Pay Pal button, there is a transfer to the system website where the payment takes place. Everything works fine, but it doesn’t work on iPhones, it just redirects to an empty basket, what could be the reason, I read about the cache, but at the moment there is no cache on the site at all, what can I catch on to? I will be grateful for any help.