Hi @Brynn Juanarena,
Thank you for posting your question on Microsoft Q&A Community. We're happy to help you with your concern.
Regarding to your question, if you accidentally marked an email as phishing in Microsoft 365, it can be reversed. Here’s how you can undo it:
- Go to your Junk or Deleted folder and locate the email.
- Right click on the email and click Report > Not junk to reverse the action.
- If you reported it as a phishing, Right click on it and click Restore
If the email is in Quarantine: (You'll need administrator permission to do this)
- Visit the Microsoft 365 Security & Compliance Center: https://security.microsoft.com
- Navigate to Email & Collaboration > Review > Quarantine.
- Find the email you reported.
- Select the email and click Release message.
- Then choose Submit the message to Microsoft to improve protection (false positive) to notify Microsoft and restore the message.
Hope my information helps. Please reach back again if you need further assistance.
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