Hello,
I have managed to find some information pertaining to your situation, which I hope may be of assistance to you.
If you replace all of the sign-in security information, there's a 30 day waiting period for the changes to take effect. During this time, you can still access most Microsoft services, but you won’t be able to do things that require a security or verification code.
From What does “Security info change is still pending” mean? - Microsoft Support
When all security info is removed from a Microsoft account, the account is put into a restricted state for 30-days.
While we understand this 30-day period might be frustrating, this is done to protect and alert you in case the security info was removed by someone who had unauthorized access to your account.
We'll send notifications during the 30-days to the original security info, which could be a phone number or email address. These notifications are sent to alert you that changes were made to your security info.
If you still cannot access the account, you can try the Account restatement form Microsoft-Services Account Reset
Once you start to register a new Number make sure to put in a secondary authentication method Like the App or Alternate Email Address.
Reference:
Didn't know updating security info would take 30 days... - Microsoft Community
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