Hi Lisa Gilly,
Welcome to Microsoft Q&A forum.
I understand how frustrating it is when emails don’t show up in the Inbox as expected.
To quickly identify what’s going on, please confirm the two points below:
- Which Outlook are you using to view your email: Outlook.com on the web (browser) or the Outlook app (New/Classic) / mobile?
- Please sign in to Outlook on the web (Outlook.com) with the same account. Do the missing emails still not appear in the Inbox—for example, do they show up in Junk Email, Deleted Items, Archive, or the Other tab (if Focused Inbox is enabled)?
- Does this happen with all senders, or only specific senders / specific email threads?
Once I have that information, I can guide you through adjusting the specific settings so new emails consistently appear in your Inbox.
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