error pop up on estimate shipping

Hi,
I am running a dual language site. www.ladeuxiemechance.com/webstore. If I go to view basket/ estimate shipping, in English it all works ok. However if I swap languages to French and select estimate shipping I get a pop up with the following:

SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data
OK
{"shipping_method":{"weight":{"title":"Exp\u00e9dition bas\u00e9e sur le poids","quote":{"weight_5":{"code":"weight.weight_5","title":"Colissimo ()","cost":"11.00000","tax_class_id":"0","text":"11,00\u20ac"}},"sort_order":"1","error":false},"pickup":{"title":"Retirer","quote":{"pickup":{"code":"pickup.pickup","title":"Retirer vos achats chez La Deuxieme Chance","cost":0,"tax_class_id":0,"text":"0,00\u20ac"}},"sort_order":"2","error":false}}}

Seems to work ok if I simply pass the order as usual. Any suggestions please???

Same issue
viewtopic.php?f=114&t=213650&p=764008#p764008

xxvirusxx I did as you originally suggested and it was working ok. Now I am getting a pop up that wasn't there with the original problem which was that nothing was happening. I have checked and it is still as you suggested.