mail.parspack.co has no CNAME records.
Question and response
Question
dig mail.parspack.co. NS
Answer
The response has no answer records.
Authority
parspack.co. 3278 SOA ns21.cloudns.net. support.cloudns.net. 2022102605 7200 1800 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0