An authenticator app can fail in different ways.
You may still see six-digit codes, but every code is rejected. Microsoft Authenticator may stop sending approval prompts. Your accounts may disappear after moving to a new phone. Or the app may simply freeze or crash.
These problems need different fixes.
Before changing anything, make sure you have another way to sign in. Do not remove accounts, clear app storage, uninstall the app, or reset the phone until you know how you will recover access.
First, identify what is actually failing
Use the symptom that matches your problem.
| What you see | What to check first |
|---|---|
| Six-digit codes are rejected | Phone time, correct account, old MFA registration |
| Microsoft approval prompt never arrives | Internet, notifications, battery restrictions |
| Codes disappeared on a new phone | Backup, sync, or transfer |
| Requests still go to the old phone | Old authentication method is still registered |
| QR code will not scan | Camera permission, expired QR code, app version |
| App freezes or crashes | App update, Android update, cache, storage |
| Only a work or school account fails | Organization policy, work profile, device registration |
This step matters because reinstalling the app will not fix every kind of Authenticator problem.
Before you remove or reset anything
Check whether you still have at least one recovery option.
That could be:
- backup or recovery codes
- SMS or email verification
- a security key
- another trusted device
- access to the old phone
- an already signed-in browser
- another authentication method
- an IT administrator who can reset MFA
If you have none of these, avoid destructive changes.
Clearing cache is usually safe.
Clearing storage or app data is not the same thing. It can remove local Authenticator information.
If your six-digit codes are rejected
When the app still generates codes but the website says they are wrong, start with time and account matching.
Check automatic date and time
On many Android phones, open:
Settings > System > Date & time
Turn on:
- Set time automatically
- Set time zone automatically
On Samsung phones, the path is usually:
Settings > General management > Date and time
Restart the phone after changing the setting.
Then wait for a completely new code before trying again.
A time-based code can fail when the phone clock is even slightly out of sync.
Make sure you are using the correct account
Authenticator apps can contain several entries with similar names.
Check the:
- email address
- service name
- organization name
- duplicate entries
- old and new registrations
A code from an old registration can look perfectly normal and still be rejected.
Re-register only if you still have account access
If every new code fails and you can still open the account through another sign-in method, remove the old Authenticator registration from the account’s security settings and add it again.
Do not delete the Authenticator entry first unless you are certain you can sign back in.
If Microsoft Authenticator approval prompts do not arrive
Microsoft Authenticator approval requests depend on internet access and background notifications.
The six-digit code may still work even when push approvals are broken.
Check the internet connection
Try both Wi-Fi and mobile data.
Also disconnect a VPN temporarily.
If approvals work on one network but not another, the problem is likely the network, VPN, proxy, or firewall rather than the Authenticator account itself.
Check notifications
Open:
Settings > Apps > Microsoft Authenticator > Notifications
Make sure notifications are allowed.
Then request a new sign-in attempt.
Do not rely on an old approval request because it may already have expired.
If notifications are failing across several apps, use Android Notifications Not Working? How to Fix It instead.
Check Do Not Disturb
Turn off Do Not Disturb or similar focus modes temporarily.
Request a new approval.
If the prompt appears, adjust the focus settings instead of permanently disabling them.
Check battery restrictions
Open:
Settings > Apps > Microsoft Authenticator > Battery
Make sure the app is not heavily restricted in the background.
Depending on the phone, you may see options such as:
- Unrestricted
- Optimized
- Restricted
- Allow background activity
For testing, choose the option that allows Authenticator to run normally in the background.
Check background data
Open the app’s mobile-data settings.
Make sure background data is allowed.
Also check whether Data Saver is blocking Authenticator.
This is especially useful when approval prompts work on Wi-Fi but not on mobile data.
Check Google Play services
Microsoft Authenticator push notifications can depend on Google Play services on Android.
Make sure Google Play services and Google Play Store are installed, enabled, and working.
If Play services keeps crashing, use Google Play Services Keeps Stopping? How to Fix It.
Update Authenticator and Android
Open Google Play Store and update the Authenticator app.
Also install any available:
- Android updates
- Google Play system updates
- Google Play services updates
- Company Portal updates, if your workplace uses it
Restart the phone after important updates.
Then request a fresh sign-in attempt.
If the Authenticator app freezes or crashes
A crashing app is a different problem from rejected codes.
Try these in order:
- Force stop the app.
- Reopen it.
- Restart the phone.
- Update the Authenticator app.
- Update Android.
- Check free storage.
- Clear the app cache.
To clear cache on Android:
Settings > Apps > Authenticator > Storage & cache > Clear cache
Do not choose Clear storage or Clear data unless you already know how your accounts will be restored.
For a safer explanation of cache versus app data, see How to Clear Cache on Android Without Losing Data.
Google Authenticator codes are not working
Google Authenticator mainly generates time-based codes.
If the codes are rejected:
- Check automatic date and time.
- Wait for a fresh code.
- Make sure you selected the correct account.
- Check whether the service recently changed your MFA setup.
- Re-register the account only if you still have another way to sign in.
Once an account is configured, internet access is not normally required just to generate a TOTP code.
Google Authenticator codes are missing on a new phone
If you use Google Authenticator with Google Account sync enabled, signing in with the same Google Account on the new device can restore synchronized codes.
If you did not use sync, transfer the accounts manually while you still have the old phone.
Transfer from the old phone
On the old device:
- Open Google Authenticator.
- Open the menu.
- Choose Transfer accounts.
- Choose Export accounts.
- Select the accounts.
- Generate the transfer QR code.
On the new phone:
- Install Google Authenticator.
- Choose Transfer accounts.
- Choose Import accounts.
- Scan the QR code from the old phone.
- Test the transferred codes.
Keep the old phone until you confirm the new one works.
If the old phone is lost
This becomes an account-recovery problem.
Check whether the service offers:
- recovery codes
- SMS
- email verification
- a security key
- another trusted device
- account recovery
- administrator-assisted MFA reset
If your Google Authenticator codes were synchronized, they may reappear after you sign in with the same Google Account.
If they existed only on the lost phone and were never synced or transferred, reinstalling the app cannot recreate them by itself.
Microsoft Authenticator not working after changing phones
Microsoft Authenticator backup and restore does not behave the same for every account type.
Some accounts restore more completely than others.
You may find that:
- third-party TOTP accounts restore their codes
- personal Microsoft accounts require sign-in again
- work or school accounts appear but need re-registration
Seeing Action required after a restore does not automatically mean the recovery failed.
Complete the re-registration for that account.
Approval requests still go to the old phone
Adding Authenticator to a new device does not always remove the old one.
First make sure the new phone can authenticate successfully.
Then remove the old device from the account’s security methods.
Do not simply uninstall Authenticator from the old phone and assume it has been removed from the account.
For work or school accounts, your organization may require you to use its security-information page or contact IT.
Only a work or school account fails
When personal accounts work but a work account does not, the problem may be organization-specific.
Possible causes include:
- device registration
- Conditional Access
- work-profile problems
- Company Portal compliance
- required PIN or biometrics
- old device registration
- organization security policy
If only the work account fails, do not factory-reset the phone.
Contact IT and give them the exact error message.
Check the Android work profile
A work profile can behave like a separate environment from the personal side of the phone.
Make sure:
- the work profile is enabled
- Authenticator is installed in the correct profile
- the profile is not paused
- Company Portal is current
- the required PIN or biometric is configured
- the device is marked compliant
A working personal Authenticator account does not prove the work-profile copy is configured correctly.
QR code will not scan
Try these simple checks:
- Update the Authenticator app.
- Allow Camera permission.
- Clean the camera lens.
- Increase the brightness of the screen showing the QR code.
- Make sure the full code is visible.
- Move the phone slightly closer or farther away.
- Generate a fresh QR code if the setup page may have expired.
Do not scan an authentication QR code sent by an unknown person.
A QR code used for Authenticator setup can contain the secret that generates your verification codes.
Treat manual setup keys the same way.
Reinstall Authenticator only after recovery is confirmed
Reinstalling the app should be one of the last steps.
Before you uninstall it, make sure at least one of these is true:
- backup or recovery is verified
- Google Authenticator codes are synchronized
- the old phone still works
- recovery codes are available
- another sign-in method works
- you are still signed in and can re-register MFA
- an administrator can reset MFA
A reinstall can repair a damaged app installation.
It cannot restore a local secret that was never backed up, fix an old server-side MFA registration, or automatically remove an old phone from the account.
Never approve an unexpected request
An approval prompt you did not trigger is not an app problem.
Do not approve it.
Instead:
- Deny the request.
- Change the password from a trusted device.
- Review recent sign-in activity.
- Remove unfamiliar sessions.
- Review registered security methods.
For a work or school account, report suspicious prompts to your IT or security team.
Avoid these mistakes
Do not:
- clear Authenticator storage before checking recovery
- delete every account from the app
- factory-reset the phone as an early fix
- remove the old phone before testing the new one
- repeatedly request approval prompts
- approve requests you did not start
- scan authentication QR codes from strangers
- share recovery codes or setup keys
- assume reinstalling will restore everything
The best fix depends on what failed.
Rejected codes usually point to time, account selection, or an old registration. Missing Microsoft approval prompts usually point to notifications, network access, battery restrictions, or Google Play services. New-phone problems usually need backup, sync, or transfer rather than a reinstall.
Start with the symptom that matches your case, and avoid destructive changes until you know how you will recover access.
