Hi @Taneeta,
Thank you for posting your question to the Microsoft Q&A forum.
According to your concern, the behavior you are seeing typically indicates that you are in the recipient's email block list or the recipient Outlook has a rule to interfere the email flow.
To troubleshoot this, please confirm with your colleagues the following things:
- Check their junk mail folder
- Select Settings > Mail > Junk email.
- Select your email to unblock and select the trash bin icon
- Check Outlook mail rules
Outlook rule can perform specific actions on email that arrives in the inbox.
- In new Outlook, select Settings at the top of the page.
- Select Mail > Rules.
- Verify if your colleagues have any rules running currently.
Note: Please understand that our initial response does not always resolve the issue immediately. However, with your help and more detailed information, we can work together to find a solution.
I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.
Thank you for your patience and your understanding. If you have any questions or need further assistance, please feel free to share them in the comments on this post so I can continue to support you.
I look forward to continuing the conversation.
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