ns2.optimaitalia.com has no MX records.
Question and response
Question
dig ns2.optimaitalia.com. MX
Answer
The response has no answer records.
Authority
optimaitalia.com. 600 SOA ns1.optimaitalia.com. noc.optimaitalia.com. 1229842180 10800 3600 604800 38400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0