Thank you for your time and patience throughout this issue!
From the screenshots you provided, the Security Info page is used for MFA and during SSPR, which is why
You cannot use the email you sign in with. As mentioned in the SSPR Prerequisites -
SSPR only works for cloud users in Azure AD, so Microsoft Accounts or personal email addresses (yahoo, gmail, etc.) won’t work on the
https://aka.ms/sspr page. For more info.
In order for your Gmail users to reset their passwords, they'll need to go to the source of authority which would be Gmail/Goggle. For more info.
How does the password reset process work?
If you'd like the ability for SSPR to accept personal accounts, I'd leverage our User Voice forum and create a feature request, so our engineering team can look into implementing this. I'll also create an internal feature request, so our engineering team can be aware of this as well.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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