Backup you Authenticator on your old phone

1. click 3 lines on top left of Microsoft Authenticator
2. click settings
3. under Backup turn on iCloud Backup

Restore

1. on your new phone open authenticator and select “restore from backup”
2. you now need to sign in to each account and rescan the QR code. 1st sign in to each account using your old phone’s Microsoft Authenticator, then after you have signed in go to https://aka.ms/mfasetup
3. Click “Add sign-in method”
4. Click “Microsoft Authenticator”
5. After adding the new Authenticator to this account delete the old Microsoft Authenticator that is pointing to your old phone

An even better option is to switch to Google Authenticator which doesn’t have this stupid step.

• when you select Microsoft authenticator in step 4 above, on the next screen you can choose “I want to use a different Authenticator app”