Hello, thank you for reaching out to Microsoft Q&A.
If you no longer have access to your alternate security information, such as your recovery phone number or email address, you will need to replace it first.
On the Verify your identity screen, select "I don't have any of these" and follow the prompts to update your security information.
Note - If you remove all of your previous security info and replace it with something new, your account will be put into a restricted state for 30 days.
You will only be able to sign in on your mobile device after 30 days.