Lost Activities and fail to sync with latest GC update

Lumia 950 Windows Phone, GC 3.15.00, Garmin fenix 3 HR (sw 4.2).

With the latest update of the GC app, I fail to sync from my phone anytime I have an activity pending. When I sync from GC 3.15.00 on my windows 10 PC, the sync is successful.
On the phone, the sync will start, then the red bar appears and indicates a failed sync. I notice that the daily steps are often updated by this process, and around 1/3 of the time, the activity becomes forever lost. In other words, I can still see the activities on the watch, but when I connect from the PC and successfully sync, one or more of the pending activities are missing. Further successful syncs never bring them back in the GC app or on the web.

I was going to capture a screen shot to attach with this post, and inadvertently discovered a potentially related factor. I run daily on a treadmill, with one or both of Garmin HR chest strap and Garmin foot pod. Today, I started a walking activity (without the extra devices), and realized that the activity synced on the phone just fine. Is there a chance that the data being generated by one of these auxiliary devices is causing the sync failure?

I've already tried reinstalling the app three times. In the second reinstall, I never saw the sync bar (either to indicate syncing or to display a failure), but the daily steps would still be updated (without activities). In this third reinstall, I'm losing data more often, so I'm going to try one more time.

I'm pretty frustrated by the lost data. An asynchronous two-phase-commit could easily protect against data loss during most kinds of failure, including app crash. I'm wondering why this doesn't seem to have been used in the Garmin Connect app.

Any suggestions on how I can improve my experience without abandoning Garmin or my phone would be appreciated.
  • Work Around

    I've noticed this as well, and while it's not possible to get back the daily heart rate data you can recover the FULL data for your activity:

    1. Plug your phone into your pc and it'll appear as drive (like a removable usb drive).
    2. Go to the activities folder and copy off the .fit file that corresponds to the time of your activity.
    3. Open your browser and go to https://connect.garmin.com
    4. Click the person icon in the left bar, and then click import data.
    5. Follow the instructions and provide the fit file when prompted.

    Obviously far from ideal, but at least you can recover your activity data.
  • Thanks - it worked!

    Thanks! I was able to recover my 7 mile run from this weekend, and 5 more over the past month.