Are you checking on the body of the email for the word or ? or in the subject
I use this quite a bit to check for scam words and then apply a wrapcode based on a decision of the words in the body
like this

and the decision expression looks something like this
If(IsSet(Email.Message.body), Contains(Email.Message.body, "The message you sent to no-reply"), false)
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Andy Jackson
Ten Lifestyle Management Limited
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