mail.123ce.fr has no CNAME records.
Question and response
Question
dig mail.123ce.fr. NS
Answer
The response has no answer records.
Authority
123ce.fr. 10800 SOA dns17.ovh.net. tech.ovh.net. 2026021700 86400 3600 3600000 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0