Additional file-related features and issues within Microsoft Teams for business
Dear Julian Spencer,
I understand that you can see the files normally in the Teams channel, but they are not appearing in your locally synced folders, while other SharePoint files continue to sync as expected.
Please note that files uploaded to a Teams channel are stored in the team’s SharePoint location rather than your personal OneDrive. The OneDrive sync app is then used to sync that SharePoint content to your computer.
For reference: File storage in Microsoft Teams
Welcome to share any updates when you have time if you need further help on this case. Thank you very much for your valuable time and your cooperation.