SMTP error from remote mail server after end of data

Hi All @asmecher

OJS 3.3.0.11

sagara@ihra.cmb.ac.lk
host ASPMX.L.GOOGLE.COM [142.250.101.27]
SMTP error from remote mail server after end of data:
550-5.7.1 [72.46.128.210 19] Our system has detected that this message is
550-5.7.1 likely suspicious due to the very low reputation of the sending
550-5.7.1 domain. To best protect our users from spam, the message has been
550-5.7.1 blocked. Please visit
550 5.7.1 Why has Gmail blocked my messages? - Gmail Help for more information. q3-20020a170902dac300b001ae16575085si3804629plx.597 - gsmtp

Reporting-MTA: dns; server002.myfastestserver.com

Action: failed
Final-Recipient: rfc822;sagara@ihra.cmb.ac.lk
Status: 5.0.0
Remote-MTA: dns; ASPMX.L.GOOGLE.COM
Diagnostic-Code: smtp; 550-5.7.1 [72.46.128.210 19] Our system has detected that this message is
550-5.7.1 likely suspicious due to the very low reputation of the sending
550-5.7.1 domain. To best protect our users from spam, the message has been
550-5.7.1 blocked. Please visit
550 5.7.1 Why has Gmail blocked my messages? - Gmail Help for more information. q3-20020a170902dac300b001ae16575085si3804629plx.597 - gsmtp

Return-path: <editor@jhssrnet.com>
Received: from [::1] (port=59274 helo=server002.myfastestserver.com)
by server002.myfastestserver.com with esmtpa (Exim 4.96)
(envelope-from <editor@jhssrnet.com>)
id 1pzztE-00427E-0e
for sagara@ihra.cmb.ac.lk;
Fri, 19 May 2023 13:11:24 +0000
MIME-Version: 1.0
Date: Fri, 19 May 2023 19:11:23 +0600
From: “Prof. Dr. Widji Astuti, SE, MM., CPM.A” <editor@jhssrnet.com>
To: sagara@ihra.cmb.ac.lk, sagara@ihra.cmb.ac.lk
Subject: Request for the Manuscript Publication Fee
User-Agent: Roundcube Webmail/1.6.0
Message-ID: <4b043dc10063c5c05c181dd01179c318@jhssrnet.com>
X-Sender: editor@jhssrnet.com
Organization: Journal of Humanities and Social Science Research
Content-Type: multipart/mixed;
boundary=“=_30bf7961c6ca01aacbd6b86363d913e9”
X-Exim-DSN-Information: Due to administrative limits only headers are returned