AnkiWeb media syncing incident 2019-06-05
Some users who synced today may have encountered error messages, or files uploading again that were previously uploaded.
The underlying issue has now been resolved. No earlier data was lost, but AnkiWeb may not have successfully recorded media changes that you made in today's sync. If you synced today and had any media changes, please go into the preferences screen of Anki and log out, then click on the sync button again. After entering your username and password, Anki will do a complete comparison of your local collection and the collection on AnkiWeb, and send and receive any files that are missing. If you have a lot of media files, the check may take some time.
Apologies for the inconvenience, and if you encounter any further issues, please let us know.