postqueue -p出現奇怪的訊息... - Linux

寄出去完全沒問題
也沒有錯誤訊息
但是每個客戶都有收到唯讀一家客戶都一直沒收到信
感覺是他們的server把我們的信給擋掉了
結果昨天寄的信今天早上他們才收到...

我用postqueue -p查了一下訊息
(host 對方主機[對方IP] refused to talk to me: 554-對方主機 554 Your access to
this mail system has been rejected due to the sending MTA's poor reputation.
If you believe that this failure is in error, please contact the intended
recipient via alternate means.)

554這個訊息是啥意思阿?

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