sib.gov.do has no MX records.
Question and response
Question
dig sib.gov.do. MX
Answer
The response has no answer records.
Authority
sib.gov.do. 3600 SOA a.dns.hostway.net. hostmaster.sib.gov.do. 2023081821 172800 900 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0