Displaying event date in site search results – fatal error

I am using echo eo_format_event_occurrence() in a theme loop to display the event date, works well for my custom event archives but not for the site search which gives a fatal error.

Hope you can help!

Fatal error:  Uncaught Exception: Error in formating DateTime object. Expected DateTime, but instead given boolean in ~/wp-content/plugins/event-organiser/includes/event-organiser-utility-functions.php:31
Stack trace:
#0 ~/wp-content/plugins/event-organiser/includes/event-organiser-utility-functions.php(164): eo_format_datetime(false, 'F j, Y')
#1 ~/wp-content/themes/~/index.php(57): eo_format_event_occurrence()
#2 ~/wp-includes/template-loader.php(77): include('/Users/admin/Do...')
#3 ~/wp-blog-header.php(19): require_once('/Users/admin/Do...')
#4 ~/index.php(17): require('/Users/admin/Do...')
#5 {main}
  thrown in <b>~/wp-content/plugins/event-organiser/includes/event-organiser-utility-functions.php</b> on line <b>31</b><br>
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