Are you using Cloud Storage, a folder shared across your home network, or an external drive for your Project files or for your Material Library?
Several Cloud/shared/external storage products are believed to have contributed to lost files and lost parts of files.
The Sync behavior for these types of storage devices could break live links.
That’s where I’d look first.
The second place I would look is the antivirus, malware and firewall systems to see if they are working, scanning or gluttonous with resources.