since a few hours mails sent to my server will not recieved. Instead the sender gets the following mail:
This is a system-generated message to inform you that your email could not be delivered to one or more recipients. Details of the email and the error are as follows:<l***@u******>: host n**1.****.tld [**.**.***.**] said: 554 5.7.1 <l***@u*******>: Relay access denied (in reply to RCPT TO command) Reporting-MTA: dns; st43p00im-zteg10063501.me.comX-Postfix-Queue-ID: AE81AC80840X-Postfix-Sender: rfc822; firstname.lastname@example.orgArrival-Date: Mon, 7 Sep 2020 18:50:37 +0000 (UTC)Final-Recipient: rfc822; l***@u******Original-Recipient: rfc822;l***@u******Action: failedStatus: 5.7.1Remote-MTA: dns; n**1.****.tldDiagnostic-Code: smtp; 554 5.7.1 <l***@u******>: Relay access denied
Does anyone has a solution for this mess?
Through Mail Log and postfix config I don't saw any problematic entries ....
Best & thanks to all!