All-in-One event calendar not displaying events in backend

Using version 2.3.12 of the All-in-One event calendar plugin, and I am having issues with it displaying all of the events under the “All Events” list in the back end. I recently changed dates of some of the events to update it for the current year, and after I did that some of my events are not displaying in the list. I can see the events on the calendar, and they display fine, but I need to figure out how to fix this, because it is causing a lot of issues for the people who update the events, it adds a lot of extra time.

So could someone please let me know how to fix this if you’ve experienced it, or if the developers know how to fix this issue?
Thanks.