nsrevprov.dns.sfr.net has no MX records.
Question and response
Question
dig nsrevprov.dns.sfr.net. MX
Answer
The response has no answer records.
Authority
dns.sfr.net. 86400 SOA nspriprov.dns.sfr.net. support.dns.sfr.net. 2025090200 10800 3600 1814400 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0