Watch unlock no longer working - prompt disappears immediately

For the past few days, the watch unlock has stopped working.

The WatchOS prompt to double-click the side button pops up on-screen but immediately disappears again before I have chance to click the button.

I'm not sure exactly when it started, but it has persisted through the last few days of Nightly updates. I've also updated WatchOS to the latest version 11.0 recently, but haven't yet updated macOS to Sequoia.

1Password Version: 1Password for Mac 8.10.48 (81048005)
Extension Version: Not Provided
OS Version: macOS Sonoma 14.7
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