mail.laboxy.fr has no CNAME records.
Question and response
Question
dig mail.laboxy.fr. NS
Answer
The response has no answer records.
Authority
laboxy.fr. 134 SOA dns108.ovh.net. tech.ovh.net. 2026021600 86400 3600 3600000 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0