_ext.funio.com has no CNAME records.
Question and response
Question
dig _ext.funio.com. NS
Answer
The response has no answer records.
Authority
funio.com. 294 SOA ns1.io-servers.com. admin.io-servers.com. 2026012801 86400 7200 3600000 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0