Hi,
I have more accounts on my whm server and one of my costumer has problem with his emails. Many of his partners get this answer from our server:
"
This message was created automatically by mail delivery software.
A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:
[email protected]
(ultimately generated from a****[email protected]****t.hu)
host gmail-smtp-in.l.google.com [142.250.102.26]
SMTP error from remote mail server after end of data:
550-5.7.1 [**********12] Our system has detected that this message is
550-5.7.1 likely unsolicited mail. To reduce the amount of spam sent to Gmail,
550-5.7.1 this message has been blocked. Please visit
550-5.7.1 https://support.google.com/mail/?p=UnsolicitedMessageError
550 5.7.1 for more information."
I check it in email logs , and the strange thing is that my costumer get every email twice, one is goes wrong and get this answer, and one is accepted.

In the accepted email information everything seems normal

But in the other email something goes wrong with the gmail, but neither the sender nor the receiver has anything to do with gmail.

the other accounts are working fine.
Thanks for helping me!
I have more accounts on my whm server and one of my costumer has problem with his emails. Many of his partners get this answer from our server:
"
Tárgy: | Mail delivery failed: returning message to sender |
Dátum: | Mon, 12 Sep 2022 20:53:07 +0200 |
Feladó: | Mail Delivery System <[email protected]********t.hu |
Címzett: | [email protected]***b.hu |
This message was created automatically by mail delivery software.
A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:
[email protected]
(ultimately generated from a****[email protected]****t.hu)
host gmail-smtp-in.l.google.com [142.250.102.26]
SMTP error from remote mail server after end of data:
550-5.7.1 [**********12] Our system has detected that this message is
550-5.7.1 likely unsolicited mail. To reduce the amount of spam sent to Gmail,
550-5.7.1 this message has been blocked. Please visit
550-5.7.1 https://support.google.com/mail/?p=UnsolicitedMessageError
550 5.7.1 for more information."
I check it in email logs , and the strange thing is that my costumer get every email twice, one is goes wrong and get this answer, and one is accepted.

In the accepted email information everything seems normal

But in the other email something goes wrong with the gmail, but neither the sender nor the receiver has anything to do with gmail.

the other accounts are working fine.
Thanks for helping me!