Dear @S0305621,
Thank you for posting your question in the Microsoft Q&A forum.
As a moderator, I don't have the tools to investigate your specific account directly. Because this is a user-to-user support forum. Moderators, contributors including external Microsoft employees cannot directly intervene in Microsoft product features or access back-end systems. Our role is limited to providing technical guidance on reported issues, requests, or ideas. However, I will try my best to guide you as clearly as possible.
To provide you with better support, could you please help me answer a few questions below:
Could you help me check Outlook Web and the New Outlook to see if you are experiencing the same issue there?
Do you have the Outlook app on your phone? Please check if the issue happens there as well.
What type of account are you using? (Exchange/IMAP/POP)
You mentioned that you aren't receiving any mail at all, does that mean you aren't even receiving emails from people within your own organization?
If you receive mail on your phone/web browser, then the problem is the Outlook Desktop App.
If you don't receive mail anywhere, then the problem is the Mail Server or Storage Quota.
With your help, I will try to pinpoint the exact issue you are facing.
I look forward to your support and response!