RTH-BKB-ROVH.corp.wznet.com.br has no CNAME records.
Question and response
Question
dig RTH-BKB-ROVH.corp.wznet.com.br. NS
Answer
The response has no answer records.
Authority
corp.wznet.com.br. 5689 SOA dns-aut-01.corp.wznet.com.br. cgr.wznet.com.br. 2026020223 300 3600 3600 38400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0