mail.multiplicnet.com.br has no CNAME records.
Question and response
Question
dig mail.multiplicnet.com.br. NS
Answer
The response has no answer records.
Authority
multiplicnet.com.br. 4295 SOA ns1.valueserver.com.br. lucas.multiplicnet.com.br. 2026020703 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0