Woocommerce Cart empty

Dears,
On page http://www.regence.be/categorie-produit/catalogue-du-18-novembre-2017/
Select 1 product
Select Téléphone and click AJOUTER A MON CATALOGUE
Then, close popup
You can see 1 ARTICLE was added to the Woocommerce card.
Now click in the menu 1 Article and there you can see it says the WP cart is empty…it was working yesterday, I don’t understand…
Thank you,
pierre

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