Hi,
today I did the Zwift Insider VOTuesday Micro Races and for the 2nd time Race 3 doesn’t show up in Activities. Not in Strava, too. But it does show up on Zwift Power. I had the same thing last time.
Is it under 2km in distance?
I can’t say for sure. Each race lasts 4 minutes and then ends. Because of the incline in that race, it might have been under 2 km for me.
That would explain it if it were the case. Rides under 2km are not saved as activities.
Ah ok. Could very well be. In that case, I need to ride faster to make it at least 2 km. 
But I didn´t manage that in Group B. So that must apply to quite a few other people too.