I can't delete event on watch even though it no longer shows on Garmin Connect. My body battery thinks it an event day everyday. What do I do?

Best is reset the watch , or else wait until the date has past. Sometimes the event doesnt delete from watch. I have reported to supported previously.

If you need to reset , read this first

forums.garmin.com/.../some-advice-before-upgrading-replacing-a-watch-or-a-hard-reset