mail.ticklink.com has no CNAME records.
Question and response
Question
dig mail.ticklink.com. NS
Answer
The response has no answer records.
Authority
ticklink.com. 25 SOA dns21.hichina.com. hostmaster.hichina.com. 2026010913 3600 1200 86400 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0