Mail delivery failed: returning message to sender

Good morning, I have a problem with my e-mail, unfortunately when I try to send an e-mail to another address containing a return message in the form of 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: adress] all hosts for 'onet.pl' have been failing for a long time (and retry time not reached) Reporting-MTA: dns; ************* Action: failed Final-Recipient: rfc822; ************ Status: 5.0.0 2020-07-13 13:35:05 1juwVA-004oIn-6l Sender identification U=csgdansk D=csgdansk.pl S=noreply@csgdansk.pl 2020-07-13 13:35:05 1juwVA-004oIn-6l == przemek96@opoczta.pl R=dkim_lookuphost T=dkim_remote_smtp defer (-53): retry time not reached for any host for 'opoczta.pl' 2020-07-13 13:35:05 1juwVA-004oIn-9D Sender identification U=csgdansk D=csgdansk.pl S=noreply@csgdansk.pl 2020-07-13 13:35:05 1juwVA-004oIn-9D == michal3103@onet.pl R=dkim_lookuphost T=dkim_remote_smtp defer (-53): retry time not reached for any host for 'onet.pl' 2020-07-13 13:35:05 1juvNE-004l1V-7K Sender identification U=csgdansk D=csgdansk.pl S=noreply@csgdansk.pl 2020-07-13 13:35:05 1juvNE-004l1V-7K == hasajacykacperek@icloud.com R=dkim_lookuphost T=dkim_remote_smtp defer (-53): retry time not reached for any host for 'icloud.com' 2020-07-13 13:35:05 End queue run: pid=1145152 2020-07-13 13:35:23 SMTP connection from (User) [185.234.217.193]:54719 closed by QUIT 2020-07-13 13:39:27 SMTP connection from [185.234.217.193]:55875 (TCP/IP connection count = 1) 2020-07-13 13:39:27 no host name found for IP address 185.234.217.193 2020-07-13 13:39:28 SMTP connection from [127.0.0.1]:50602 (TCP/IP connection count = 2) 2020-07-13 13:39:30 SMTP connection from [127.0.0.1]:50602 closed by QUIT 2020-07-13 13:39:30 SMTP connection from [127.0.0.1]:35120 (TCP/IP connection count = 2) 2020-07-13 13:39:30 SMTP connection from (localhost) [127.0.0.1]:35120 closed by QUIT 2020-07-13 13:39:47 SMTP connection from (User) [185.234.217.193]:55875 closed by QUIT 2020-07-13 13:40:05 cwd=/ 2 args: /usr/sbin/exim -bpu 2020-07-13 13:43:49 SMTP connection from [185.234.217.193]:57015 (TCP/IP connection count = 1) 2020-07-13 13:43:49 no host name found for IP address 185.234.217.193 2020-07-13 13:44:09 SMTP connection from (User) [185.234.217.193]:57015 closed by QUIT 2020-07-13 13:44:28 SMTP connection from [51.15.6.79]:45554 (TCP/IP connection count = 1) 2020-07-13 13:44:29 SMTP connection from [127.0.0.1]:51150 (TCP/IP connection count = 2) 2020-07-13 13:44:31 SMTP connection from [127.0.0.1]:51150 closed by QUIT 2020-07-13 13:44:31 SMTP connection from [127.0.0.1]:35672 (TCP/IP connection count = 2) 2020-07-13 13:44:31 SMTP connection from (localhost) [127.0.0.1]:35672 closed by QUIT 2020-07-13 13:45:05 cwd=/ 2 args: /usr/sbin/exim -bpu 2020-07-13 13:46:08 H=mail.namagesy.de [51.15.6.79]:45554 sender verify defer for : Could not complete sender verify callout: mail.namagesy.de [51.15.6.79] : Connection timed out 2020-07-13 13:46:08 H=mail.namagesy.de [51.15.6.79]:45554 F= temporarily rejected RCPT : Could not complete sender verify callout 2020-07-13 13:46:09 SMTP connection from mail.namagesy.de [51.15.6.79]:45554 closed by QUIT 2020-07-13 13:48:12 SMTP connection from [185.234.217.193]:57939 (TCP/IP connection count = 1) 2020-07-13 13:48:12 no host name found for IP address 185.234.217.193 2020-07-13 13:48:32 SMTP connection from (User) [185.234.217.193]:57939 closed by QUIT 2020-07-13 13:50:05 cwd=/ 2 args: /usr/sbin/exim -bpu 2020-07-13 13:50:06 SMTP connection from [127.0.0.1]:51790 (TCP/IP connection count = 1) 2020-07-13 13:50:08 SMTP connection from [127.0.0.1]:51790 closed by QUIT 2020-07-13 13:50:08 SMTP connection from [127.0.0.1]:36312 (TCP/IP connection count = 1) 2020-07-13 13:50:08 SMTP connection from (localhost) [127.0.0.1]:36312 closed by QUIT