Uninstallation unsuccessful

Hello, friend.

We’ve been using this plugin for a testing environment, and we don’t need it anymore. It was when we uninstalled this plugin that we found out that every post that had a [custom-field] shortcode in it crashed. More specifically, “the_content()” function was returning null. The worst part is that it still returns null even if we delete the shortcode. However, if we reinstall the plugin, everything works again, despite the fact that we’re not using any shortcode or function related to the plugin anywhere on the site.

What changes did this plugin do to the posts exactly? How do I undo them? Please understand that re-creating the posts is not a solution, as I have lots of them.

By the way, the plugin is great and it serves its purpose perfectly well. I really like it and recommended for many unexperienced users.

But right now, I need the plugin uninstalled and am forced to keep it for no reason, Please help!

https://wordpress.org/plugins/get-custom-field-values/