Diagnostic-Code: 5.7.1 Service unavailable

Diagnostic-Code: 5.7.1 Service unavailable

Hello
Some of our mail receivers (@hot.ee) blocked zoho's IP. Is there anything we can do? Added autoreply.txt with longer autoreply e-mail/error message.
Diagnostic-Code: 5.7.1 Service unavailable; Client host [136.143.188.52] blocked using cbl.mailcore.local; Blocked by cbl.mailcore.net
Remote-MTA: dns; mx.dka.mailcore.net