ups.net.do has no MX records.
Question and response
Question
dig ups.net.do. MX
Answer
The response has no answer records.
Authority
ups.net.do. 21600 SOA dns1.cscdns.net. hostmaster.cscdns.net. 2013030804 56341 28170 394387 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0