The solution is: add the DQOS key to mailcow.conf, then create an extra.cf under /data/conf/postfix and add the following content there:
smtpd_recipient_restrictions =
reject_rhsbl_sender xxxxxxx.dbl.dq.spamhaus.net=127.0.1.[2..99],
reject_rhsbl_helo xxxxxxx.dbl.dq.spamhaus.net=127.0.1.[2..99],
reject_rhsbl_reverse_client xxxxxxx.dbl.dq.spamhaus.net=127.0.1.[2..99],
reject_rhsbl_sender xxxxxxx.zrd.dq.spamhaus.net=127.0.2.[2..24],
reject_rhsbl_helo xxxxxxx.zrd.dq.spamhaus.net=127.0.2.[2..24],
reject_rhsbl_reverse_client xxxxxxx.zrd.dq.spamhaus.net=127.0.2.[2..24],
reject_rbl_client xxxxxxx.zen.dq.spamhaus.net=127.0.0.[2..255]
Sorry for my bad English 😃