mx02.avertis.net has no NS records.
NS records for this zone are defined at avertis.net.
NS records for this zone are defined at avertis.net.
Question and response
Question
dig mx02.avertis.net. NS
Answer
The response has no answer records.
Authority
avertis.net. 600 SOA dns20.ovh.net. tech.ovh.net. 2026021800 86400 3600 3600000 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0