mercur.o2it.ro has no MX records.
Question and response
Question
dig mercur.o2it.ro. MX
Answer
The response has no answer records.
Authority
o2it.ro. 3600 SOA neptun.o2it.ro. abuse.o2it.ro. 2021051201 7200 540 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0