mail.interlink.ad.jp has no CNAME records.
Question and response
Question
dig mail.interlink.ad.jp. NS
Answer
The response has no answer records.
Authority
interlink.ad.jp. 1513 SOA dns1.interlink.or.jp. root.interlink.ad.jp. 2024101701 86400 900 86400 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0