[Plugin: FAQ Manager] fatal error wp_trim

Hello I am receiving the following error in the faq manager admin dashboard. I believe it is preventing all of my topics from displaying. I have tried to increase the trim words amount from 15 to 100 in the code but this doesn’t seem to help. I have also taken out the origin faq question and answers and replaced them with test as question and test as answer. Please help.

Fatal error: Call to undefined function wp_trim_words() in D:\Hosting\8459899\html\shcitizeninfo\wp-content\plugins\wordpress-faq-manager\faq-manager.php on line 132

http://ww.wp.xz.cn/extend/plugins/wordpress-faq-manager/