Odd Emails into the Inbox

I created a mail rule to receive email into my DTPO inbox. So far it works as I set it up: the subject of the message has to begin with “DT:”. I have received, however, a couple of messages that I should not have. They use capital letters in the subject, but not “DT:” and they do not start with “DT:”. Any tips on what might be causing this and how I might resolve it?

A screen grab of your rule as you set it up inside Apple mail (presumably), would certainly help being able to identify where the problem might be.

Here they are. In both cases I have selected “to DevonThink Pro” which the screen shot does not show.
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