Restore Office 365 Inbound Email

I have a Microsoft 365 tenant where Exchange Online suddenly stopped receiving messages for every domain we host. Outbound mail flows fine, but nothing arrives in any inbox—no bounce-backs, no NDRs, just silence. Because of that, I suspect the problem sits in DNS: MX, SPF, DMARC, or a mis-directed record that broke mail routing.

I need someone who can jump into the Exchange admin center, review the domain setup, and trace the path from public DNS through Microsoft’s front-end to the mailbox. You are free to use the usual toolset—PowerShell, Microsoft Remote Connectivity Analyzer, dig/nslookup, or whatever you prefer—as long as we get a clear root-cause analysis and a fast fix.

Acceptance criteria:
• Correct DNS changes published and propagated (MX, SPF, DKIM/DMARC if required).
• Test messages from external services land in all tenant mailboxes.
• Short hand-over note summarising what was wrong and the exact records added or modified.

I can grant temporary admin access and provide registrar or hosting logins for DNS editing as soon as we agree to proceed. Let me know how quickly you can take this on and how long you expect propagation and validation to take.