Hi @Karl Heisenberg
1.If you no longer have access to the phone number or email address, or you need to add another way to sign in, select I don't have any of these when trying to sign in and follow the prompts.
2.If you can still access your Microsoft account through another device, go to the Security Info page. Update your phone number and add alternative verification methods like an email address or an authenticator app.
3.If you’re using a work or school account, contact your IT administrator. They can update your verification methods and help you regain access.
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