Hello Hannah,
Thank you for posting your question in the Microsoft Q&A forum.
I understand how incredibly frustrating this loop is. The good news is that this error is usually a browser or network conflict, not an issue with your account itself. Since you are using the old iPhone (a trusted device) on the same Wi-Fi, the system might be getting confused by old, cached credentials or a network glitch.
Here is how to force that request through and resolve the situation:
Step 1: Switch Networks and Browser Mode
- Turn OFF Wi-Fi on your phone and use 4G/5G Mobile Data instead.
- Open your browser (Safari or Chrome).
- Open a New Private Window (Safari) or Incognito Tab (Chrome)
Step 2: Trigger the Security Replacement Process
Now, repeat the steps you were trying before in this new window. With the Private Mode + Mobile Data combination, this button should now work without the red error.
Step 3: The 30-Day Wait
Once you click Next successfully:
- The system will ask for a new email address or phone number where they can contact you in 30 days.
- Your account will enter a security hold for 30 days. This cannot be expedited by support agents.
- On Day 30, the old, inaccessible Authenticator app will be removed from your account automatically. The new email/phone you provided will become your new login method. At that point, you will be able to set a new password and finally add the account to your new iPhone.
Please give the Private Mode/Mobile Data method a try and let me know if it allows you to submit the request.
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