If your Google Authenticator codes are not working, you are not alone. Invalid or expired 2FA codes are one of the most common authentication problems. This guide explains the most common causes and how to fix them step-by-step.
In This Guide
Common Reasons Google Authenticator Fails
1. Time Sync Is Incorrect
Authenticator apps rely on your device’s time being perfectly synced. If your phone clock is even a few seconds off, the generated code may be rejected.
- Enable automatic date and time in device settings
- Restart your device
- Ensure timezone is correct
2. Code Has Expired
Each code is valid for only 30 seconds. If you wait too long before entering it, the login attempt will fail.
3. Wrong Account Selected
If you have multiple accounts saved, make sure you are using the correct one.
4. Secret Key Was Entered Incorrectly
If the account was manually added and the secret key was mistyped, codes will never match.
How to Fix Time Sync Errors
On Android:
- Open Google Authenticator
- Go to Settings
- Select “Time correction for codes”
- Tap “Sync now”
On iPhone:
- Go to Settings → General → Date & Time
- Enable “Set Automatically”
What If You Lost Your Phone?
If you lost your device and cannot access your authenticator app:
- Use backup codes provided during setup
- Use a previously registered device
- Contact the service provider for identity verification
For detailed recovery steps, see our guide: Lost Phone With 2FA Enabled.
Wrong Account Selected or Mistyped Secret Key
If none of the above fixes resolve the issue:
- Double-check the original QR code or secret key
- Disable and re-enable 2FA on the account (if possible)
- Ensure no VPN or firewall is interfering
Google Authenticator App Crashes or Won't Open
If the Google Authenticator app itself is crashing or failing to load, try these steps:
- Force stop the app — On Android: Settings → Apps → Google Authenticator → Force Stop. Relaunch it.
- Clear the app cache — On Android: Settings → Apps → Google Authenticator → Storage → Clear Cache. This does not delete your accounts, only temporary files.
- Update the app — An outdated version may have compatibility issues. Check the Play Store or App Store for updates.
- Reinstall only as a last resort — Uninstalling Google Authenticator without first exporting your accounts will lock you out. If reinstalling is necessary, export accounts first (three dots → Transfer accounts → Export accounts).
Transferring Google Authenticator to a New Phone
Google Authenticator syncs to your Google Account by default since the 2023 update. If you are signed in to your Google Account in the app, your codes should restore automatically on a new device after signing in.
If automatic sync is off, use the built-in transfer feature:
- On your old phone: open Google Authenticator, tap the three-dot menu, select Transfer accounts → Export accounts.
- Choose the accounts to transfer and tap Next. A QR code is generated.
- On your new phone: open Google Authenticator, tap the three-dot menu, select Transfer accounts → Import accounts, and scan the QR code.
If you no longer have access to your old phone, you will need to use backup codes for each service or go through account recovery.
Re-Enrol Google Authenticator From Scratch
If nothing else works, the most reliable fix is to remove Google Authenticator from an account and re-add it. This process varies by service but is generally:
- Sign in to the account using a backup code (saved when you first set up 2FA) or through the account recovery process.
- Go to Security settings and disable two-factor authentication temporarily.
- Re-enable 2FA and scan the fresh QR code with Google Authenticator.
- Save the new backup codes.
This is time-consuming if you have many accounts set up, but it fully resets the authenticator and eliminates any sync or configuration issues.
Security Reminder
Never share your secret key or backup codes with anyone. Legitimate services will never ask for your 2FA code outside the login process.