Hi Dennis,
Thanks I can able to see the issue now. Look like there is a missing translation on the event page. Can you add the below translation to your EasySocial frontend language file?
COM_EASYSOCIAL_PAGE_TITLE_EVENTS_FILTER_ONGOING="Ongoing Events"
Also, if you want to change the browser title of this page, you can do it at file 'JOOMLA/components/com_easysocial/views/events/view.html.php' and look for line start from 181 ~ 307 and look for the php code similar to below:
FD:: page()->title(JText::_('COM_EASYSOCIAL_PAGE_TITLE_EVENTS_FILTER_ONGOING'));
The FD:: page()->title() is the one that setting the page title
Hope this help and have a nice day!