Events not showing

It seems that since the new version the event calendar stopped working correctly. Because of the holiday there were not much of events so i don’t know when it is happened.

The issue is that when a visitor clicked on a event it is rediercted to the url but that results in a 404 error.
I can see the calendar event in the calendar view, when i go over it a popup with the information is showed.

I disabled all the plugins, but the issue still exists. Is this a known issue?

Placing messages and blogs are no problem, the urls there work just fine.
Also older events are not shown correctly anymore.

Hope someone can help. This is the link

https://www.ads-software.com/plugins/the-events-calendar/