Lost your two-factor codes after a new or lost phone
Authenticator codes often stay behind when you change phones. Each account has its own way back, and some are slow.
What's usually going on
Apps like Google Authenticator and Microsoft Authenticator keep their codes on the phone unless backup was turned on. A normal phone transfer doesn't always bring them across. If the old phone still works, the fix is easy. If it's lost or wiped, you recover each account separately.
Worth trying first
Don't wipe the old phone.
If you still have it, keep it working until every account is moved. In the authenticator app, look for a transfer or export option.
Check whether backup was on.
Google Authenticator can sync codes to your Google account, and Microsoft Authenticator has cloud backup. Install the app on the new phone and sign in with the same account to see if the codes return.
Look for backup codes.
Many services gave you a list of one-time backup codes when you turned two-factor on. Check your password manager, printouts, and downloads.
Use each account's recovery route.
On the sign-in page, choose an option like "Try another way" or "I can't use this method". Some accounts send a text or email instead; others take a few days.
Set it up properly this time.
Turn on backup in the authenticator app, save new backup codes somewhere safe, and add a second way in for each important account.
When to hand it over
If several important accounts are affected, or one of them is your email or bank. Recovery has to be done in the right order. Some services can't restore an account once every method is gone, and we'll say so if that's the case.
Your own technologist, on call.
Tell us a little about your setup. We'll take it from there.