If you've added your Facebook App ID and App Secret and bumped into the error
Make sure to check the correct App ID and App Secret that is configured on the Facebook Setting in Hybrid Connect.
Also, make sure that the Added App ID and App Secret does not have white spaces before and/or after the code.
If you can't solve the problem with the above solution, try this one too
Log out of Facebook, Clear cache from browser, then go back to Facebook, and your site, try again.This sounds like You have may an expired or non-working access token.
If you're still having problems after doing the suggestions above, please send us a ticket.