sergipe.ns.porkbun.com has no MX records.
Question and response
Question
dig sergipe.ns.porkbun.com. MX
Answer
The response has no answer records.
Authority
ns.porkbun.com. 1800 SOA alagoas.ns.porkbun.com. dns.cloudflare.com. 2397577138 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0