mail.fst-pay.it has no CNAME records.
Question and response
Question
dig mail.fst-pay.it. NS
Answer
The response has no answer records.
Authority
fst-pay.it. 60 SOA dns101.ovh.net. tech.ovh.net. 2025012311 86400 3600 3600000 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0