Wi-fi won't reconnect on waking from sleep

[Tachybaptus]

This is a brand new computer. When it sleeps and wakes up, it won't reconnect to my wi-fi. I tested it with a different connection, a wi-fi hotspot on my phone, and it wouldn't connect to that either.

Apparently this is a known HP fault experienced on laptops two years ago -- see
https://h30434.www3.hp.com/t5/Notebook-Wireless-and-Networking/Wifi-disconnects-after-being-in-sleep...

I tried to follow the steps suggested on this page, and went to Device Manager > Network Adapters, opened the wi-fi adapter, went to Properties > Power Management, and switched off 'Allow the computer to turn off this device to save power'. This didn't fix the trouble.

The Network and Internet Troubleshooter couldn't identify the problem either.

Another solution mentioned on this page was to go to the HP Support Assistant and download new drivers. The pane for Software & Drivers said that updates were available, and made a list of them. But here I ran into another problem. As soon as I tried to select all the updates listed (or to select any of them individually) the list simply disappeared. So the Support Assistant isn't working properly either.

Meanwhile, the computer updated itself to Windows 10 version 2004 and this seemed to solve the disconnection problem, maybe by installing a new driver. I put the Power Management setting back to the default -- i.e. it does allow the computer to turn off the adapter to save power -- and it was still waking up OK.

But that happy result lasted only one day, and now the wi-fi problem has come back just as before. And the fault in the Support Assistant continues.

Can you suggest a solution to either or both these problems?