메일인증시 스팸으로 분류? 채택완료

인증메일인것 같은데... 스팸으로 분류 되었다고 메일이 되돌아 옵니다.

이유가 뭘까요?

실제로 새로 가입하는 회원들은 메일인증이 잘 되고 있는데...

반송되는 해당 이메일 주소는 이미 가입된 회원이거든요...

여러분들의 조언 부탁드립니다.

The original message was received at Mon, 27 Sep 2021 09:37:05 +0900
from localhost [127.0.0.1]

  ----- The following addresses had permanent fatal errors -----
<*****@hanmail.net>
   (reason: 554 5.7.1 DAS41 ***.***.21.135: Your mail is blocked automatically by anti-spam system. (E04))

  ----- Transcript of session follows -----
... while talking to mx2.hanmail.net.:
>>> DATA
<<< 554 5.7.1 DAS41 ***.***.21.135: Your mail is blocked automatically by anti-spam system. (E04)
554 5.0.0 Service unavailable

attach(1).txt

Reporting-MTA: dns; OOO.net
Received-From-MTA: DNS; localhost
Arrival-Date: Mon, 27 Sep 2021 09:37:05 +0900

Final-Recipient: RFC822; *****@hanmail.net
Action: failed
Status: 5.7.1
Remote-MTA: DNS; mx2.hanmail.net
Diagnostic-Code: SMTP; 554 5.7.1 DAS41 ***.***.21.135: Your mail is blocked automatically by anti-spam system. (E04)
Last-Attempt-Date: Mon, 27 Sep 2021 09:37:06 +0900