You are probably here because your mail to me bounced. The error message says something about a blacklist.

This error message is a catch-all error message and also comes when the server sending the email looked like it's not a real mail server. This can happen for various reasons, for example if the reverse lookup in the DNS was not set up.

If you fix that and you are still blacklisted, then maybe you spammed me in the past (I'm vindictive when it comes to spam).

There is no procedure to get unlisted.

If you try to work around a ban here via phone or contacting my company, you as a person (not just your MX) will be persona non grata for perpetuity. I run a zero tolerance policy in that respect.

Practically the only way to be personally blacklisted on my system is continuing to send me mails after I told you twice to not send any more mails. There is no procedure to get unblocked after that. This is by design.