Strings translation

Hi, I am writing you about translation of the text strings of theme. On the site https://www.villatozzolihouse.com, at the foot, I inserted an index of the pages that I proceeded to translate into three languages ​​(Italian, English and Spanish). It would seem that, some weeks ago, some links translated by me are skipped and, in the English and Spanish versions, sometimes the redirect leads to the pages in Italian. As in the past, I opened the string translation page but, to my surprise, it is not possible to view English and Spanish translations. I can only see translations in Italian. How can I intervene on strings? Is it possible to intervene on existing translations via FTP? Or is there a solution to reactivate the display of the three different languages ​​in this section?
Thank you in advance for your attention. My best regards.

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