Garmin Vivomove Style not recording multiple activities?

No, never had such a problem on my Luxe. Have you already tried to connect the watch to your computer and having a look at the "activities" folder to find out whether it has really not recorded the activities or just the sync hasn't worked? I've had such problems every now and then with my Edge 520. Also, sometimes it takes some time for Garmin Connect to update the activity list so that suddenly one or few days later, new ones show up.

Thanks, but I tried that, per Garmin support, but for the Vivo Style, for some reason, there is not an activities folder. There's an empty "activity" folder... I've been limiting myself to two activities at a time in between syncing to the phone. 

Well, crud. I just walked a mile on the treadmill before running. This time it saved the walk, but not the run.

I also don’t have that experience. When in the Gym, I start and stop each activity. So treadmill, rowing, etc each starting and stopping. All activities end up in Garmin Connect. As fwmone said; it does take a little while, but ony a few minutes after synching in my experience. Just to be sure: after the activity, you tap twice on the watch and press the green “button” on the screen?

Resetting the watch might be worth a try, I guess.