mail.edu.do has no MX records.
Question and response
Question
dig mail.edu.do. MX
Answer
The response has no answer records.
Authority
mail.edu.do. 3600 SOA ns1.ikexie.net. web.thancloud.com. 2020122901 7200 1800 1209600 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0