Attempting to hide past events creates error

Event Booking version 2.1.1
Joomla! 3.5.1 Stable

When I go into the 'Configuration' and set 'Hide Past Events' to 'Yes' and after clicking 'Save' I am returned with an error:
(the browser tab says 'Error: 404 Category not found')
"The requested page can't be found.

An error has occurred while processing your request.

You may not be able to visit this page because of:

an out-of-date bookmark/favourite
a mistyped address
a search engine that has an out-of-date listing for this site
you have no access to this page"

Any reason why this happens?

That's really strange. However, as you know, version 2.1.1 is quite old now, you should update your site to latest version 2.7.0 and check it again

I don't think this error related to Events Booking code base. It might be something related to your server

Tuan