How to Solve mautic.ERROR: [MAIL ERROR] Expected response code 354 but got code "554", with message "554 5.5.1 Error: no valid recipients

Product Support
1

My Mautic version is: 3.0.1
My PHP version is: 7.2.30

My problem is: Mails are not sending. I tried to “Send test email” and got this error
Expected response code 354 but got code “554”, with message "554 5.5.1 Error: no valid recipients "

The Connection test was a success.

Please help.

2

Nevermind, this error is due to my mail server dns not fully propagated. After a day, it was working fine.