Apple Watch (series 5) not synching calendars since WatchOS 9.1

I upgraded my Watch OS to 9.1 a few weeks ago, and since then, calendar appointments do not appear to be syncing. Whatever was on my calendar before the upgrade date is still in synch, but no appointments added to my various Google calendars that are accessible via my iPhone and Mac native calendars do not update to my watch.

Using the Watch app "Reset Sync Data" temporarily fixes the problem by pushing what's currently on my Mac and iPhone calendars to my watch. But it's not addressing the underlying issue.

I've thought about trying a full reset. What is the implication? Will I be able to restore everything to my watch thereafter? Any other ideas?

Thank you.

- David