Using New Outlook on Windows for personal email, calendar, and contact management
Welcome Adam Rombach,
Thank you for reaching out to Microsoft Q&A. I understand why being prompted to secure the account again after you had already blocked the attempts and changed your password would be frustrating.
Two-step verification is intended to add another layer of protection to a personal Microsoft account. Microsoft explains that even if someone obtains the password, they should still be stopped if they cannot complete the second verification method. How to use two-step verification with your Microsoft account
Since you have already changed your password, I recommend checking the account's recent activity before making further changes:
- Sign in to https://account.live.com/Activity
- Review the recent sign-in entries and expand any activity you do not recognize.
- If an entry wasn't yours, select the available option to report or secure the account.
Regarding the additional security prompt occurring approximately 12 hours later, I don't want to speculate about the specific reason it was triggered because that information isn't visible to community users.
I hope this helps clarify the purpose of two-step verification and gives you a way to confirm whether the account is currently secure.