Wrong page title

Hi,

Question about the The Events Calendar, i’m using the plugin on this website:
http://studiovtestsite.nl/marnixgymnasium/agenda/

The last activity I added is “December” Why is title of that item used as page title?

I would like to have there “Agenda” of something similar.

Rick

http://wordpress.org/extend/plugins/the-events-calendar/