Hello Jonna ,
Thanks for reaching out in the Microsoft Q&A!
Unfortunately, without access to your old phone or backup codes, transferring your accounts from the old Microsoft Authenticator app to the new one isn't possible. You can either recover your accounts through alternative verification methods provided by each service or re-enroll with Microsoft Authenticator by initiating the enrollment process again on each website or service. Ensure to set up a backup method for your new Microsoft Authenticator app to avoid future lockouts.
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