Does anyone know how to reject an email received through mailgun (mailgun.com)? As a comparison, a similar service, cloudmailin allow you to return a status code of 404 or 403 to reject an email, and the sender of that email will receive a delivery failure notice. I am trying the same with mailgun, however, mailgun will attemp to redeliver with longer and longer interval once it receive the 404 or 403 status code.
What I have tried: Mailgun documentation doesn't say anything about this. Mailgun support is not responding to my emails.
If I got an answer from mailgun I will post it here as an update.
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