problem after update v2.0

Warning: require_once(Phpmailer/PostsmtpMailer.php): failed to open stream: No such file or directory in wp-content/plugins/post-smtp/Postman/Postman.php on line 67

Fatal error: require_once(): Failed opening required ‘Phpmailer/PostsmtpMailer.php’ (include_path=’wp-content/plugins/post-featured-image-generator/library/SWL:/wp-content/plugins/post-featured-image-generator:wp-content/plugins/post-featured-image-generator/library:.:/:/usr/local/php71/lib/pear’) in /2016/wp-content/plugins/post-smtp/Postman/Postman.php on line 67