Update causes PHP Fatal Error

My Web Hosting provider sent me an email and they found this in our logs:

PHP Fatal error: Call to undefined function relevanssi_purge_excerpt_cache() in /var/www/html/ti/tibesar.com/wp-content/plugins/relevanssi/lib/indexing.​php on line 215, referer: http://tibesar.com/wp-admin/post.php?post=7186&action=edit

Thought you’d like to know…

https://ww.wp.xz.cn/plugins/relevanssi/