pbx.simtelecom.com.br has no NS records.
NS records for this zone are defined at simtelecom.com.br.
NS records for this zone are defined at simtelecom.com.br.
Question and response
Question
dig pbx.simtelecom.com.br. NS
Answer
The response has no answer records.
Authority
simtelecom.com.br. 300 SOA dns1.commcorp.net.br. postmaster.commcorp.com.br. 2022102255 7200 900 1296000 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0