Feature unavailable: Facebook Login is currently unavailable for this app.

If you see the message –> Feature unavailable: Facebook Login is currently unavailable for this app after clicking the Facebook login icon, it’s due to Facebook’s Data Use Checkup that Facebook introduced recently. To get your Facebook login working again, log in to your Facebook developer dashboard, you will see the notification. After that, you just need to click the notification and everything else is self-explanatory from there.