Using Classic Outlook on Windows for personal email, calendar, and contact management
Hi TereflegnMesele,
Thanks for your reply, I suggest you can click Block Sender to add the sender to your Blocked Sender list.
As I previous said, our email messages are automatically protected against spam and malware by EOP, and quarantine holds potentially dangerous or unwanted messages. Once we confirm that our valid messages are not quarantined. we just need to keep these spams or phish emails in Quarantine, by default, the message is reported to the Microsoft Spam Analysis Team. Depending on their analysis, the service-wide spam filter rules might be adjusted to allow the message through.
In addition, if you are an administrator, you can configure some anti-spam policies to protect your org, here is the detailed reference: https://docs.microsoft.com/en-us/microsoft-365/security/office-365-security/configure-your-spam-filter-policies?view=o365-worldwide#configure-end-user-spam-notifications also, Microsoft Office 365 Advanced Threat Protection (ATP) is a good choose, reference for you: https://docs.microsoft.com/en-us/office365/servicedescriptions/office-365-advanced-threat-protection-service-description
Hope it is helpful to you, have a nice day:)
Thanks,
Linda