ns4.6level.fr has no CNAME records.
Question and response
Question
dig ns4.6level.fr. NS
Answer
The response has no answer records.
Authority
6level.fr. 3293 SOA ns1.openprovider.nl. dns.openprovider.eu. 2025112108 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0