mail.waves.jp has no CNAME records.
Question and response
Question
dig mail.waves.jp. NS
Answer
The response has no answer records.
Authority
waves.jp. 252 SOA name.technowave.ad.jp. bind-admin.technowave.ad.jp. 2025030371 10800 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0