When switching languages from English to Greek, the text from add to cart button disapears

[pganotis]

Hi everyone,
I am using prestashop 1.6.1.8 and i have set this site: premiumfoods.shop with the default theme.

After almost completing the shop, there was a decision for the site to be translated to Greek also. So I installed the Greek language pack.

At the front office when i change the language from English to Greek, on the featured products on the homepage, the text from the "add to cart" button disappears where the button itself is right there..

I do not know what sort of problem is it since i have tried to check all of the possible translations. 

Thank you