faqoi.oi.com.br has no NS records.
NS records for this zone are defined at oi.com.br.
NS records for this zone are defined at oi.com.br.
Question and response
Question
dig ws-lb-38586887.sa-east-1.elb.amazonaws.com. NS
Answer
The response has no answer records.
Authority
sa-east-1.elb.amazonaws.com. 60 SOA ns-2034.awsdns-62.co.uk. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 60
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0