dns03.kbrw.fr has no MX records.
Question and response
Question
dig dns03.kbrw.fr. MX
Answer
The response has no answer records.
Authority
kbrw.fr. 600 SOA dns01.kbrw.fr. dnsmaster.kbrwadventure.com. 2026022604 7200 1800 1209600 10800
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0