Hello @Juan ManuelB-873831897 ,
Was this a document that you linked to in an email? If you need to truly break a link to a document then you'll need to call into Support, confirm the security question(s), and then our higher level technical team can go in on the back end and break it.
An alternative method, if you just need that particular document to not be seen, is to replace it - typically with a blank word document.
Please be aware any of these changes could take up to 24 hours to be the default view, and anyone who still has the document cached in their browser may see it even after its replacement until their cache is refreshed / cleared.