Alarm Notification Sender Domain Error

I am receiving this error in my logs when trying to use the alarm notification pipeline -

I am having no issues using this script -
system.net.sendEmail(smtpProfile = 'Profile 1',fromAddr="automation@msiexpress.com", subject="Test", body=body, html=1, to=recipients)

The notification block is configured as such -
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With the roster calculated like below. The "to email address" and "from email address" are the same in both the script and pipeline.
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And my notification profile, "Email 1" is set to use "Profile 1" which is tested and working through the script console.

Is there some step or setting I am missing? All other sources I can find say that error occurs because of incorrect domain or foreign characters but the same From Address is working in the script. I do notice in the field for "From Address" in the block editor there appears to be a space before the address, not sure if this is just a cosmetic issue but I am unable to remove it.

I could be wrong but it looks like there may be some leading whitespace in you From Address parameter in the email1 notification settings. You could also test creating a simpler notification pipeline to try and isolate the issue.

Yes, I noticed that as well but I'm unable to remove it. No matter what I enter into that field there is leading whitespace. I did try adding leading whitespace into the from address on my script and it still worked as expected but maybe it is not the same effect.

I'm not sure how I can make the pipeline any simpler and still test it, this is all that it is at the moment -
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I was using the Ack pipeline instead of the Active Pipeline, that error was throwing me off though.