I am unable update my new phone number and not even able get rid of my old number

If this is a personal Microsoft account:

1. Go to the Microsoft account Security page: Sign in
2. Select Manage how I sign in.
3. Select Add a new way to sign in or verify.
4. Add another available method such as a recovery email address, Microsoft Authenticator, or a passkey.

Important details:

• The option to add a new phone number may not be available for a personal Microsoft account.
• Microsoft may only show options such as a recovery email, Microsoft Authenticator, or a passkey when adding new sign-in methods.
• If verification codes are still going to the old number and access to that number is lost, select I don't have any of these during sign-in and follow the prompts to replace security info.
• To verify what security info is currently on the account, sign in to the Security page and select Update info.
• Do not keep requesting codes repeatedly, because unusual activity can temporarily block code delivery.

If the old number is already linked elsewhere, a phone number can only be added to a single Microsoft account. If the number was recently used on another account, the only option is to use a different mobile number. In some cases, the Transfer option appears only after 30 days.

If this is a work or school account:

1. Open the Security info page: Sign in
2. Select Update info.
3. If another method still works, use it to sign in.
4. Add the new phone number as a sign-in method, then remove the old one.
5. If only the old phone number is offered and there is no access to it, choose I don't have any of these to replace security info.

If sign-in cannot be completed because only the old number is available, the organization’s Microsoft 365 administrator or IT help desk must reset MFA methods.

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