Update Lagging

I have updated all of my plugins including Gravity Forms and the newest version of WordPress, but the only one that seems to update forever is Gravity PDF. The first time it was over 10 minutes. I tried refreshing and going to a different page and it first gave me a blank white screen saying, “Briefly unavailable for scheduled maintenance. Check back in a minute.”

I then restored a backup of the site and tried again, and after 20 minutes of waiting, it’s now giving me this error upon refresh:
“Fatal error: require_once(): Failed opening required ‘/home/****/public_html/gandydancer3/wp-content/plugins/gravity-forms-pdf-extended/vendor/autoload.php’ (include_path=’.:/usr/lib/php:/usr/local/lib/php’) in /home/****/public_html/gandydancer3/wp-content/plugins/gravity-forms-pdf-extended/src/autoload.php on line 39”

Any issues I should look for?

https://www.ads-software.com/plugins/gravity-forms-pdf-extended/