FTP Test by Garmin is totally wrong and not the Standard Protocol?

There are nuances to differing FTP test procedures. I am not sure about Garmin. You need to do your testing with the training program that you are using consistently. If, in this case, Zwift - do your FTP testing in Zwift. If TrainerRoad, etc.

sure, i do, but as Zwift, Trainer Road, etc can't deliver Training Effect, vo2max dircetly to the Garmin Eco System, i record it twice with Edge, think Garmin have to change it, that it nearly looks like the other Test, they are all identical, the main 20 minutes, ride as hard as possible you can hold for the 20 minutes, only the Warm up is sometimes a little bit different.

And of course, there is the possibility to do the Test outdoor, so you have only the Garmin Test, or you import a training, that you can follow, or?

for me, it's not a nuances when i have to ride the last 8 minutes 50% over my actual FTP, a colleague of mine have the same problem!

Why don't you enter your Zwift/TR FTP into Garmin Connect manually? All Garmin's metrics should pick it up the same way as if you had it from Edge's test.

What should Garmin correct???

There is no right or wrong FTP test. And you really don't need to do a test to find out your FTP. The important thing is to warm up and then ride as hard as you can so that you can ideally last 40 minutes at that pace. Obviously you have to pace yourself to not hit the wall after the first 5 minutes. But if you just ride for fun, why do you need to know your FTP anyway?? If I were you and would ride for fun, I would rather focus on my bpm and learn to ride using the rate of perceived exertion to make sure you stay healthy. If you can't ride over your FTP for a couple of minutes, than the FTP you set is too high.

Doing multiple FTP tests is only useful or interesting if you really follow the progress and study the numbers - and in that case you should use a smart trainer to always test under the same conditions

to correct it, so it is possible to fnish it without failing the Test, the Lactate Threshold Test for running works as it have to work, this test protocol is the wrong way.

my FTP is correct, but i never heard, that in a FTP Test you have to ride more ore less the half of the time 50% over your FTP!

i do sport (road cycling) for fun since more of my half life (30 years), with a big break (4 years) cause of an accident, since one year i am back and working on structured trainings for Duathlon (thats fun for me).

Why i have to work with my bpm when i am able to work with power and structured trainings?

This is what I do.

You don't make any sense - if you know your FTP and you are saying your FTP is correct, why are you bothering with the FTP test? If you are doing the FTP test outside, how can it "force" you to ride 50% over your FTP? It might be a suggestion of the workout - but if you can't hit those numbers, that's it. If you are doing it on a trainer, you can't use ERG mode......so I really don't get what you are talking about.

Power meters record your wattage - and while it might be cool to impress other cyclists with a high FTP, that's it. BPM is actually telling you if you are harming your body. You are even saying, the FTP is wrong and doesn't work and someone from Garmin should change it...well, you don't really strike me as someone that is used to train with a power meter. BTW, my coach mixes my training between wattage and REP/bpm focused all the time.

The FTP test on the Edge uses logic provided by Firstbeat. It looks at your HR settings (check those values are correct) and your current FTP value. It then performs a ramp test and will take you above your FTP level. It is looking for changes in your HRV data. 

You may find it incredulous, but the free Garmin Connect IQ app by Xert really works.  It's totally free.  No need to sign up for anything.

https://www.dcrainmaker.com/2017/07/xert-rolls-out-free-real-time-ftp-app-on-garmin-devices.html