Same issue here on iOS 27.2 (installed Sep 24) with an [iPhone model] and a MacBook. iPhone to Mac clipboard works after a restart, then silently stops after a while. Mac to iPhone keeps working the whole time. Toggling Bluetooth, Wi-Fi, and Handoff on the phone did nothing for me either. I found a workaround that’s faster than rebooting: Settings > Battery > Power Mode > flip the Adaptive Power toggle. Either direction works. Turn it off if it’s on, or on if it’s off, and you can flip it right back to where it was. Universal Clipboard from iPhone to Mac starts working again immediately. Plugging the phone into a charger also brought it back once, which makes me think any power-state change is what restarts whatever service handles the Handoff advertising. It’s a reset rather than a fix, since it goes quiet again after a while, but it beats restarting the phone every time.