May I ask which type of account are you using? Exchange, IMAP or POP?
If you are using Exchange, please go to https://outlook.office.com/mail/ and check if you can receive new emails there. If yes, the issue might come from your Classic Outlook.
You can try:
- Remove and re-add account. This will force a resync to the server.
- Rebuild your .ost file: Close Outlook > Press Windows + R > Type in %LOCALAPPDATA%\Microsoft\Outlook\ > Look for your email address and delete it > Restart Outlook.
- Create an Outlook profile - Microsoft Support
If you cannot receive new emails on Outlook web, it means that the emails never reached your mailbox.
Please check in Junk emails and Deleted items folder. If the emails are still not there, you might need to contact your IT admin and ask them to perform a message trace.
Message trace will help you check if the emails got blocked somewhere and never reached your mailbox.
Please give your IT admin this article: Message trace in the new EAC in Exchange Online | Microsoft Learn
If you are using IMAP or POP, can you please provide your provider's name? Additionally, you can check in your provider's webmail to see if the new emails there. Also, verify your port and server name.
I look forward for your reply.
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