Hello, thank you for reaching out to Microsoft Q&A.
Microsoft always recommends that users have at least three verification methods. So even if one method gets disabled or becomes inactive, you can use another method to reset your security information.
If you no longer remember your password and only you have provided with your old number for verifying your identity, replacing the phone number is the only option to regain access to your account.
That is, on the Verify Your Identity screen, select 'I don't have any of these' and follow the prompts to replace the security information.
Remember to use a familiar device from which you've frequently accessed your Microsoft account, as well as a familiar location. Microsoft will review your responses and respond within 24 hours.
Note - If you remove all of your previous security information and replace it with something new, your account will be put in to an restricted state for 30 days.
If your Microsoft account recovery request was not granted or was unsuccessful, please click the attached link for more information:
So, you can only reset your password after 30 days.