mail.int.4net.tv has no CNAME records.
Question and response
Question
dig mail.int.4net.tv. NS
Answer
The response has no answer records.
Authority
int.4net.tv. 300 SOA ns0.int.4net.tv. hostmaster.4net.tv. 2026030409 14400 3600 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0