Microsoft account team messge in correspondents

Hi Today, several emails that I have received, which I think were sent from an Outlook account, have, instead of what I would expect to see as the sender's address under correspondents, have Microsoft account team <account-security-noreply@accountprotection.microsoft.com> When I click on the email, I can see the genuine sender's address This has only happened today At least one of the emails that I received came from someone that I know uses Outlook Any ideas? Thanks