slw.nrtmexico.mx has no MX records.
Question and response
Question
dig slw.nrtmexico.mx. MX
Answer
The response has no answer records.
Authority
nrtmexico.mx. 86400 SOA ns1.mexicosystem.com. servers.privatednsorg.com. 2026022601 86400 7200 1600000 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0