Sync seems to be erasing data from FR15 (also posted in windows software > garmin express)

(pardon posting here, there doesn't seem to be a spot for forerunner 15)

Experiencing sync issues - sync seems to complete, but nothing uploaded. I then discover that all my runs are deleted.

Garmin Express: v7.25.0+a13e85b4

Forerunner 15 v2.70 Unit ID 39174-40267

0 seilogramp 10 days ago

This watch was entry level, released 11 years ago. It should have the ability to attach to a computer and view files on it that way. If so, try a manual upload from your Garmin device to Garmin Connect Web - How Do I Manually Upload an Activity I Recorded to Garmin Connect?

If you get any message other than Import Complete, then there is a problem with the file. Attach it to this thread. We can take a look to see if it is repairable.

Zip the file, then in a reply post Insert >> Image/video/file >> click Upload >> browse for file >> OK.
Or upload the fit file to a reputable file sharing service, such as OneDrive, Google Drive, Dropbox, make the file public, then paste a link to the file in your post.

I'd follow this with backup up all the activity files to a computer, then do a full factory reset.- How Do I Delete All Information From My Device? | Forerunner® 15 | Garmin Customer Support

The watch can only store up to 7 activities, then overwrites older activities.

Forerunner 15 | Garmin

After all this, try a short test running activity, sync with Garmin Express, then see if the activity is erased from the watch by connecting to a computer and viewing the \GARMILN\ACTIVITY folder. 2 years ago, GE did have an issue where it was deleting files, but that was fixed and there are no current complaints on the Garmin Express forum - Express 7.18.0 deletes all activities - Garmin Express Windows - Mac/Windows Software - Garmin Forums