Performance condition/anaerobic not working anymore

Looks ok for me on Fenix 6X Pro Solar Titanium with 19.21 BETA. Maybe the Aerobic score is a little high but its about the same as earlier similar runs. This was a fairly easy 10.63 km run with 2 shorter sprints included.

I've been using 19.20 for about two weeks and continue to get updated performance condition, VO2 and (An)aerobic numbers from my indoor cycling.

EDIT : Added another ride with 19.21b and all data present and correct. FTP got a little bump up too.

I am impressed with your anaerobic training effect number. I have to take a few days off cycling. My legs are too tired. Even low watts on my trainer make me feel as I have higher watts 

Haha! My fitness is tanking at the moment. FTP in a slump and VO2max declining. Here's the workout that gave me those numbers....

Is that zwift? I tried it last year but liked trainer road better. Then I switched to trainer day. I did not like zwift. I was riding fast but it was giving me a low speed and everybody was passing me. Very discouraging. They could have fixed the algorithm now. I do not care about avatar anyway. Sufferfest was tough. Trainer road is my favorite. They now use Ai to make you a faster cyclist. 

That is Zwift, yes. I've been using Zwift well over five years. Nothing wrong with speed calculations if you use a properly calibrated power meter and correct weight and height.

If you use a "classic" trainer (as I think they're called) instead of a power meter or smart trainer then I think there is way too much possibility of bad results. I've been using Neo trainers since day one. I also sometimes use Assioma Duo pedals. 

With proper power data I am happy with Zwift. There is so much variety on offer - training programs, individual workouts, free riding in various environments, social group rides and various racing options. I couldn't bear riding/training/exercising in the sterile environment of Trainer Road and similar. Zwift is alive. Riding with and against people keeps it interesting.

Punchy little sprint effort gained most of my anaerobic score....

I use a flight trainer from 4iiii   It uses magnets to generate the force. Very cool design and very responsive. So I do not have to take my wheel off or be sure that my tire is inflated. I am the opposite. I do not care to ride with other guys virtually. I did when I was riding outdoor though. I just like to listen to music while riding. I did use a classic trainer when I started with zwift. It was a fluid trainer. So I guess my smart trainer would work now. 

I have problems with the cardio activity, It looks like it is working when I am running, but not when doing cardio.

Which kind of activity are you using? 

Cycling for me is ok, let me know if I can do some more tests for you 

I've got the same issue as well and my device is still under warranty, what channel did you raise this with Garmin?  I want to do the same