ns72.hostgator.mx has no CNAME records.
Question and response
Question
dig ns72.hostgator.mx. NS
Answer
The response has no answer records.
Authority
hostgator.mx. 456 SOA jessica.ns.cloudflare.com. dns.cloudflare.com. 2398120691 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0