Problems with the PPCA error

Hello,
I have many sites using this plugin, and I am the admin of most. Even with the ability to log right in as a Facebook admin, where I obtain the access token, I continue to get an error. This process shouldn’t be so difficult so something must be going on. Are you hearing of errors when trying to link the accounts? Is it possibly a cache issue? I have spent a lot of time already trying to get these all working and I am not having much luck (and yes, the plugins are updated). It’s super easy to just do this right from the site’s WP dashboard, log into FB through there, and get the code. I have no idea why it doesn’t work after that and the error still shows. Please advise. Thanks.