Surface Pro 7 USB port power stops

[submitra]

Problem: Android 10 phone plugged into Surface Pro 7 (via Surface Pro 3) docking station stops charging
OS: Windows 10 Pro 21H1

I believe I need to set/reset the relevant "Allow the computer to turn off this device to save power) switch" for either
- USB SuperSpeed USB Hub, or
- Generic USB hub
- USB Root hub (USB 3.0)

I had this working, but it stopped working. Earlier, it would stop charging after about 5 mins., then I had it charging until phone was fully charged.
Now it won't charge at all.

How do I know which Power Management switch to enable and which to disable? (checked/unchecked in Device Manager)

 

[submitra]

Occasionally works, but I cannot get the setup which permits persistent charging.
For a while I thought that if the SP7 was low on battery, the USB port wouldn't output charging current, but even with the SP7 at 100% charge level, the phone won't charge at times.