I got a new phone and my sign-in code stopped working

By New Jersey IT Solutions Team · Updated 2026-10-29

Try these steps, in order

1. If you still have the old phone, keep it. Do not erase or trade in the old phone yet.
2. Add the new phone first. On a computer, go to your account security page (for Microsoft 365, sign in and open your security info). Add the authenticator app on the new phone as a new method. Approve the code from the old phone.
3. Check it works. Sign out and sign in once using only the new phone.
4. Remove the old phone. Delete the old phone from your sign-in methods. Now the old phone can be erased.
5. If the old phone is lost or broken. Ask your company admin to reset your sign-in method. They will confirm it is really you, then let you set up the new phone.

Check the clock

Codes depend on the correct time. If a code is rejected, turn on automatic date and time on the phone.

Plan ahead

Some authenticator apps can back up your accounts to the cloud. Turn that on before you ever lose a phone. Also keep a second sign-in method, like a spare number, for every important account.

Common questions

Can I get my codes back without the old phone?

Not by yourself. An admin has to reset your sign-in step, or you use a backup method you set up before.

Is it safe to turn off the second step to get in?

No. Ask for a reset instead. Turning it off leaves the account easy to attack.

What if I lost the phone?

Tell your admin at once so the account can be locked and the phone wiped of work data.

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• Outlook keeps asking for my password
• What to do with IT when an employee leaves

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