Hi @Michelle
Can you please provide your exact Outlook version? You can check this in Outlook > About Outlook.
I am testing on version 16.107.2 and did not see this behavior.
If you are not on the latest version, you can try downloading it via Update history for Office for Mac - Office release notes | Microsoft Learn.
You can try downloading version 16.107.2 or a previous version where you don't see this behavior (16.104.x)
If the issue persists, you can go to Settings > Signatures > in Replies/Forwards, change it back to None > then switch back to your signature's name.
Please try and let me know if it works for you. I look forward for your reply.
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