I want my new phone number on my account as my old one is not existing anymore

To change the phone number on the Microsoft account when the old number no longer exists, update the security info on the account and then use that updated info for BitLocker recovery.

1. Go to the Microsoft account security info management page: https://account.live.com/proofs/Manage and sign in.
2. In Security info, add a new phone number:
   • Select Add phone number.
   • Enter the new number and complete the verification steps.
3. After the new number is added and verified, remove the old phone number if it is no longer valid.

If sign-in is blocked because the only verification options are the old phone or email:

1. On the Verify your identity screen, select I don't have any of these.
2. Follow the prompts to replace the old security info with new details (new phone or email).
   • Be aware that if all previous security info is removed and replaced, the account may be put into a restricted state for 30 days while the new info is verified.

Once the Microsoft account security info is updated and access to the account is restored, use that account to retrieve or manage BitLocker recovery information as provided by the device or organization policy.

If BitLocker recovery keys were never backed up to this Microsoft account or another location, and the device is already locked, recovery may not be possible; in that case, contact the device administrator or support channel for the device.

References:

• Troubleshoot Microsoft verification code issues
• Why is Microsoft texting me?
• Change the email address or phone number for your Microsoft account
• Help with "phone number is already used" in a Microsoft account
• Use a screen reader to set up and troubleshoot multifactor authentication