Error when trying to change user of a discussion in the backend

When I open a discussion and try to change the user when I save I get this error message.

Notice: Trying to get property of non-object in /home/leagueses/public_html/plugins/finder/easydiscuss/easydiscuss.php on line 87

Warning: Creating default object from empty value in /home/leagueses/public_html/administrator/components/com_finder/helpers/indexer/adapter.php on line 560

Catchable fatal error: Argument 1 passed to plgFinderEasyDiscuss::index() must be an instance of FinderIndexerResult, instance of stdClass given, called in /home/leagueses/public_html/administrator/components/com_finder/helpers/indexer/adapter.php on line 333 and defined in /home/leagueses/public_html/plugins/finder/easydiscuss/easydiscuss.php on line 103