Ok so I too was met with this issue. After two weeks of searching far and wide. I started thinking location sharing services are directly related to iMessage. So I searched some more and stumbled upon old apple discussion forum from 2014. I could not believe it was this easy after restoring numerous devices. Step 1 turn off iMessage Step 2 turn of device while iMessage is disabled. Do not force restart device just soft restart volume up and down then slide to power off. I would wait about 60 seconds then restart device and enable iMessage. After iMessage has properly activated return to settings>iCloud>findmy and you will be a happy camper.

Ok so I too was met with this issue. After two weeks of searching far and wide. I started thinking location sharing services are directly related to iMessage. So I searched some more and stumbled upon old apple discussion forum from 2014. I could not believe it was this easy after restoring numerous devices. Step 1 turn off iMessage Step 2 turn of device while iMessage is disabled. Do not force restart device just soft restart volume up and down then slide to power off. I would wait about 60 seconds then restart device and enable iMessage. After iMessage has properly activated return to settings>iCloud>findmy and you will be a happy camper.

Did any of you above check to see under about this Mac if under serial number was showing unavailable? If so then the Apple Store could have failed to flash the replacement logic board with existing serial number which likely caused issues installing software update?

I am also assuming that's why Apple has not released any new betas due to complaints of logic board replacments causing bricked MacBooks?

Two Methods Left to Reset Your Bluetooth Hardware In macOS Monterey, there are two options for resetting your Bluetooth hardware. First, try the command line method. Open Applications > Utilities > Terminal, and enter this command: sudo pkill bluetoothd This will reset and restart the Bluetooth module in your Mac. Within about five minutes, sometimes less, your devices will reconnect and you can get back to work (or play.) If that fails to resolve the issue, you may have to go a step further. Open Finder, then click in the menu bar Go > Go to Folder. Type /Library/Preferences/com.apple.Bluetooth.plist and then press Return. The proper file should be highlighted, the plist file for your Bluetooth system. Drag it to the Trash, then reboot your Mac. This will force macOS to rebuild the configuration files for each of your Bluetooth devices. A Last-Ditch Effort to Resolve Lingering Issues If none of those methods help, there’s one more thing to try. You can unpair the troublesome device by clicking the x symbol next to it in System Preferences > Bluetooth. Be careful doing this, though, if it’s a keyboard or pointing device acting up. You’ll need another Bluetooth or wired keyboard or mouse to get the glitchy one connected again. Hopefully, in time, Apple will return the Bluetooth debug menu to its rightful place. If you want to encourage that return, let Apple know though the macOS feedback portal. Just tell them you want the “Reset Bluetooth Module” option back. Have any of you try this method Apple in previous macOS had option to debug from menu appears thats no longer the case in Monterey