_acme-challenge.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 5834933a-cd44-46bd-8ef6-35dc6153915c.2.authorize.certificatemanager.goog. NS
Answer
The response has no answer records.
Authority
2.authorize.certificatemanager.goog. 60 SOA ns-cloud-c1.googledomains.com. cloud-dns-hostmaster.google.com. 1 21600 3600 259200 60
Additional
. 0 OPT ; payload 512, xrcode 0, version 0, flags 0