Custom "subject" on Inbound Messages view

I am trying to adjust the “subject” that shows up from a Contact Form that is submitted. I am using Contact Form 7 as an “order form”, and there is not subject field that is filled out.

I have searched and saw a thread where you said you could use the following code on the “Additional Settings” tab of the Contact Form. However, when I have tried this, I still get “[your-subject]” shown in the subject column of the Flamingo Inbound Messages view.

flamingo_subject: "ccccccccccccccc"

Is this code still a viable code to use? Otherwise, is there a way to be able to get a custom subject listed there?

https://wordpress.org/plugins/flamingo/