Hi,
Thank you for sharing your question. I understand how frustrating it is to repeatedly face sign‑in prompts that reference a phone number you no longer recognize. It can be especially difficult when the security information on your Microsoft account hasn’t been updated for many years and prevents you from accessing or correcting your details. The reason this happens is that Microsoft requires verification using the existing security info before changes can be made, and if that info is outdated or inaccessible, the system may prevent updates for your protection.
The resolution in this situation is to begin the account recovery process, and if recovery isn’t possible, you may proceed with closing the account through the Microsoft account closure page, where the system will guide you based on the information available on your profile.
Would you like help drafting a message for support or guidance on walking through the recovery or closure steps yourself?
Please feel free to follow up if you need the wording adjusted or want a version tailored to customer support.
I hope this helps.
Best Regards,
Noel