Can't edit Word files sent to me opened with LO

I recently downloaded the latest version of LO when I got a new Mac and now get the following message when someone sends me a file: “The lock file could not be created for exclusive access by LibreOffice, due to missing permission to create a lock file on that file location or lack of free disk space”. I see lots of people have had this problem but I didn’t understand the answers! I’m running OS BigSur 11.3. Would be very grateful for a fix in simple language. Thanks!

How do you open the file? Do not just double click any attachment to an email sent to you, but use save file (or whatever the phrase is on your email client) first and open from the saved location.

Did you already provide Full Disk Access to LibreOffice.app? If not, check answer to question Unable to Save or Save As any document even in Safe Mode for how to do that.