Motorola Moto G 4G — Hotspot and USB tethering broken after Android security patch (dated 1 Dec 2021)

My Moto G Power (XT2041-6) uses Android 11 via Consumer Cellular, which resells ATT service.

On January 25th, I downloaded and installed the latest Android security and Google Play System patches dated December 1, 2021 (Software Version RPMS31.Q1-54-13.3-7).

Immediately thereafter, my mobile hotspot and USB tethering functions would not work. They are my only affordable means of connecting to the Internet in my semi-rural area. I’ve happily used both, especially tethering, for a few years now, previously on my old Moto E2 and now my current phone.

Three Consumer Cellular reps had no solution other than a factory reset. Note that I’ve tried unsubscribing and resubscribing to hotspot/tether, I’ve restarted the phone, and I’ve reset the Network settings, all without resolving the issue.

Also, please note that I can select both tethering and hotspot and have my computers recognize and connect to the signal, but I can't access any Websites. The only error message I've seen concerned MAC addresses not matching.

I don’t want to do a factory reset unless it’s my last resort.

I'm searching the Web and contacting forums with a borrowed WiFi connection but cannot yet find a fix. If you can recommend any source of information that might help me restore these functions, please do.

Thanks!