additional info in the notification emails

Hi,
In the payment page of mi site, there is a text-area for “additional information” that the users can fill with some comments. The thing is, I (admin) get an email notification with the details of the purchase, but the “additional information” is missed. I tried to add an item to call this “additional information” in the notification emails template, like this one for the header {{header}} , but I cannot find any shortcode (if I can say that) for this “additional information”. Please, I’ll appreciate your answer.
Thanks

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