mail.cromwellrf.com has no CNAME records.
Question and response
Question
dig mail.cromwellrf.com. NS
Answer
The response has no answer records.
Authority
cromwellrf.com. 7200 SOA ns1.elastika.pe. soporte.elastika.pe. 2025041203 7200 300 604800 7200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0