사용자 이메일 도메인이 너무 많아 작동하지 않아 Mailgun 도메인이 비활성화되었습니다: 어떻게 해야 하나요?

Ooops. Here’s the remap I meant. It’s just

  discourse remap old new

See Change the domain name or rename your Discourse.

I think that the above would work, but the UserEmails solution is probably a tiny bit better.