Fix Facebook 'Login Failed: An Unexpected Error Occurred'

Updated: 12/1/2025

You enter your password correctly, the loading circle spins, and then: 'Login Failed. An unexpected error occurred. Please try again later.' This generic error usually points to a corrupted session token on your phone, or a conflict with Apple's iCloud Private Relay (on iOS).

Table of Contents

Method 1: Clear App Storage (Not just Cache)

The login token is stored deep in the app's data files. Clearing cache isn't enough.

Android Users

Go to Settings > Apps > Facebook > Storage. Tap Clear Data. You will have to log in again, but the corrupted file will be gone.

iOS Users

Go to Settings > General > iPhone Storage > Facebook. Tap Delete App. Reinstalling it from the App Store is the only way to fully clear the data container on iPhone.

Method 2: Reset Network Settings

If your phone's SSL certificate chain is broken, it can't talk to Facebook's secure server.

Step 1: Reset

Go to Settings > General > Transfer or Reset iPhone > Reset. Select Reset Network Settings.

Note: This will delete your saved WiFi passwords, but it fixes connection handshake errors 90% of the time.

Method 3: Disable 2FA Temporarily

Sometimes the SMS code system goes down. If you are logged in on a PC, try turning off Two-Factor Authentication (2FA) in Security and Login settings, then try logging in on your phone. Once you are in, turn it back on immediately.