Thanks for the quick reply!.
I’ve added the code to my functions.php, and the plugin now redirects. Issue is, it sends me to wp-admin/admin-ajax.php with just a blank page and a 0.
I understand Wordfence might be causing the issue. So I deactivated it and it did not help. I’m also using Hummingbird and Smush Pro, in case those two plugins might be doing something.
The plugin broke randomly, it worked before with those plugins.