This error message is the bane of many social users, page owners and marketers and unfortunately just recently it has started appearing for a large number of people. I have come across this a few times in the past and the issue always seems to present itself when Facebook goes through some sort of design change.
If so you may now be presented with either one of these browser related error messages usually with a message like ERR_TOO_MANY_REDIRECTS or The page isn’t redirecting properly for www.facebook.com:
It may not happen straight away, you could have opted in months ago and Facebook has suddenly applied the new theme to your account and/or business page.
Login to Facebook by using this link: https://facebook.com/home and agree to the popup if it appears.
Hopefully this works and you are presented with a new very white theme layout. Nothing is fixed yet however, we are going to need to change back to the original theme until Facebook can fix whatever beta issue they are causing.
That's it, hopefully you can now use Facebook as normal and social posting platforms like Publer and Facebooks very own Creator Studio start working again.