udd.edu.do has no MX records.
Question and response
Question
dig udd.edu.do. MX
Answer
The response has no answer records.
Authority
udd.edu.do. 1800 SOA ns1.digitalocean.com. hostmaster.udd.edu.do. 1767081126 10800 3600 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0