ns2.onitel.com.br has no CNAME records.
Question and response
Question
dig ns2.onitel.com.br. NS
Answer
The response has no answer records.
Authority
onitel.com.br. 2335 SOA ns1.onitel.com.br. root.onitel.com.br. 20191146 28800 7200 2419200 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0