One of my colleagues have been on an extended leave (6 months+), now that he is back we decided to revisit some files we shared before he left.
To our surprise, our Chat >> Files area was completely empty.
Looking at my local \OneDrive - [CompanyName]\Microsoft Teams Chat Files\ folder, the files still seem to be stored (not sure if up to date versions, seems like some of them are older than expected)
Trying to copy one of these files back to Chat >> User >> Files gives the A file with this name already exists in this folder. What would you like to do? message, even though no files are visible in the Files tab.
Is this a known issue/feature? Does teams "clear out" old files shared in chat after some time?
I don't think it should remove them, but you should spread the word to not use these files as long term storage. The issue is you already have the file in microsoft Teams chat file so you can't drag the file or upload again. What you would do to add again is use the attach icon and OneDrive option and navigate to the Teams chat files to add it again.
The list in the chat files tab is nothing more than a breadcrumb Teams adds in there for a link to files that were shared over time, the files live in that folder or are shared where they live when you use the OneDrive option which is usually the way I like to teach users to use instead of uploading "Copies" to maintain the whole single source of truth.