Woocommerce and Polylang

Hi everybody,

I am very new to the use of wordpress…and I have a problem with Polylang and WooCommerce (sorry for my lack of originality yes).

My config
– Theme : Tesseract2
– Plugin : Woocommerce
– Plugin : Polylang
– Plugin : Hyyan WooCommerce Polylang Integration

My problem
I can :
– Check different products pages
– Add products to the cart
– Check my cart page

I can’t :
– Finalize the checkout. On the checkout page I can fill the fields related to the customers details (from name to address) and then, at the bottom of the page the sections “your order” and “payment method” are not available (endless loading) : it is impossible to finalize the checkout.

What i did so far

1- I checked a lot of discussions on internet but nothing could help
2- I tried deactivating the plugins one by one and found out that :
– The Polylang plugin is responsible for the problem (when deactivated the checkout page is working from top to bottom).
– The “Hyyan WooCommerce Polylang Integration” plugin has no impact whether activated or not.
3- I had a look at the Javascript console (google chrome browser) and fount one error “failed to load the ressource : the server responded with a status of 400 (Bad request)”. It is an error linked to a css style and I think it has nothing to do with my problem.
4-Finally I discovered something about the permalinks and I guess this is where the problem is :
a – When I go to Settings > permalinks, the “common settings” is set to “default”, so it is something like https://site_address/?p=123. With this setting I have my checkout problem. But when I switch it to “Month and Name” for example (so something like https://site_address/en/checkout/) suddenly my checkout page works…BUT…my product pages don’t work anymore : I can see them in the shop page but when I click on one of them I get a “Oops! That page can’t be found” message.

I am just beginning with WordPress but I guess the problem is maybe here.

I would like (after so many hours trying to understand, let’s say “I would LOVE”) to get your views and some help on this if possible.

Thank you very much

Tim