Apple Watch often fails unlocking Mac

My Apple Watch 10 is set to unlock my Mac Studio, both running the latest OS upgrades. It will work for a few days then stop. I will then have to go into System Systems/Login Password and try off the Apple Watch switch, then shut down my Mac, re-boot the Watch, wait for the Watch to fully connect with Wifi and Bluetooth, then re-start the Mac, go into System Settings/Login Password, and turn on the Apple Watch switch. It almost always succeeds, but then a few days or a week later, it will stop working and I'll have to do this all over again.

What gives? Anyone have any insights into why this might keep happening?

I will appreciate any advice anyone can offer.