Latitude 9420 ignores all charging thresholds

Hello,

I have Latitude 9420 and want to set some charging thresholds. I have some Latitudes in the past, so for usual I know how to proceed...

But in this case, it won't work.

The 9420 ignores all custom thresholds and all presets like Adaptive, Express, AC Power...and always charging up to 100%. In don't use a dock. I have genuine DELL 90W and 130W USB-C Charger.

First I have set the values in BIOS only (without using the PM-App), and after that I have also installed the Power Manager App (v3.10.0), but it won't work. BIOS is up to date. I also have tried to move between the thresholds and back. I have set the thresholds start at 50% and stop at 80%. Let the battery drain under 50% and plug in the charger...at the end it charges to 100%. Tried another battery give the same results.

Are any 9420 users here, which have the same problem or maybe they have not and it works?

Any ideas what's the reason? (I asume it's a BIOS bug).