smtp-isp1.foliateam.com has no CNAME records.
Question and response
Question
dig smtp-isp1.foliateam.com. NS
Answer
The response has no answer records.
Authority
foliateam.com. 300 SOA ns1.amen.fr. root.amen.fr. 2026030302 86400 7200 2592000 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0