Hello @Rossy Hii
Thank you for reaching out. I would like to inform you can restore previous authenticator app settings only if you had backed it up. If you have access to your iPhone 12 you can turn on iCloud backup and specify a Recovery account. Once done move to your iPhone 14 and use the recovery account to restore the backup from iCloud.
More details on these steps are mentioned on following article: Back up and recover account credentials in the Authenticator app
I hope this answer helps to resolve your issue.
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