Did you just delete it? I think I've seen posts people telling they are not seeing the event and "on in the next day it showed up". So I think that calendar sync is not very instant.
But no real idea, don't use that. But if you just deleted it, interesting to hear, what happens tomorrow.
Just for an additional data point - I'm seeing this same behavior. Deleted my race a few weeks ago, and in addition to still showing up in my race widget, it constantly suggests workouts for that race every day.
