My friend is paralyzed, stays isolated (due to the pandemic) at a hospital.
She uses the Lenovo YOGA 700-14ISK i5-6200U 8GB 256SSD 14″FHD with the Tobii Eye Tracker 4C since Aug 2019. The 4C is connected directly to teh USB-A port in the laptop. The laptop is always tethered to its original power supply. The laptop does not suffer from any other technical problem I could detect.
Ever since the Win 10 1909 landed the 4C is randomly stopping to track her eye movements.
It occurs 3 to 11 times a day. When in that state, it is sufficient to touch the Tobii Eyetracker toolbar on the touchscreen to wake it up. She cannot do it herself, each time she has to call a nurse.
The Win10 and all drivers have been recently reinstalled, all patches applied.
I disabled all power-saving settings I could find.
I have not found any event log entries I could associate with the occurrences.

Here is the rundown of versions:
Windows 10.0.18363.836
Tobii Device 09.07.2018 1.9.862.0
EyeChip 21.06.2006 10.0.18362.1

I generated the Tobii troubleshooting package and made it available here: https://drive.google.com/file/d/1HhaIQLpUmKDUt6lfTDorlt98qPmnhZEq/view?usp=sharing

Please advise. It is our last resort to ask for help here.