@nmegan
Hi there. So an easy fix might be to switch your trigger to focus on a folder other than your inbox, then create a rule in Outlook that looks for the same subject but then excludes any emails that have "RE:" or "FW:" at the start of the subject, and the action for that Outlook rule would be to move the message from the inbox to the folder that your flow is watching.
You could also do a condition in Power Automate to check the subject, but the above method will save you runs as it will only trigger on qualified messages.
Keep us posted.
-Ed
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