ns3.ptasp.com has no MX records.
Question and response
Question
dig ns3.ptasp.com. MX
Answer
The response has no answer records.
Authority
ptasp.com. 3600 SOA dnsbho1aut01.local. root.osscore.ptasp.com. 2021144059 14400 7200 2419200 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0