@tuanphan I have the same problem, except that if I have no excerpt, I DO want the full summary to appear. There does appear to be a glitch. If I set up an event and didn't have an excerpt, the full event summary shows on the Events List. However, if I added an excerpt then deleted it, the full event summary no longer displays.
Unfortunately, you won't be able to access the actual site since this event list is behind a Member Site paywall.
Ideally, the logic would be Show Excerpt, but if blank, Show Full Event Summary. Any ideas?