Perch Events Fatal error: Uncaught Error: Class 'PerchBlog_Cache' not found

    When linking an event to a category - the following error is thrown.


    Code
    1. Fatal error: Uncaught Error: Class 'PerchBlog_Cache' not found in /Volumes/Jobs/Websites/Mindforward/site-folder/manager/addons/apps/perch_events/runtime.php:217 Stack trace: #0 /Volumes/Jobs/Websites/Mindforward/site-folder/events/event.php(49): perch_events_event_categories('2019-05-30-reik...') #1 {main} thrown in /Volumes/Jobs/Websites/Mindforward/site-folder/manager/addons/apps/perch_events/runtime.php on line 217


    Unchecking the categories makes the error disappear.


    Can this be fixed.