Page not found when clicking on Read More

On my Calendar page that lists all the events –> I click on the plus icon to expand the event details –> I click the “Read more” link in the bottom right corner, but instead of opening the event page, I get:

Sorry, but the page you were trying to view does not exist.

It looks like this was the result of either:

    a mistyped address
    an out of date link

The “Read more” link address is

I have tried different permalink structures, but it has no effect to the event link or the issue. I have the latest Timely AOI Events Calendar installed.