c15.altospam.com has no MX records.
Question and response
Question
dig c15.altospam.com. MX
Answer
The response has no answer records.
Authority
altospam.com. 600 SOA ns1.oktey.com. postmaster.oktey.com. 1761218246 1200 3600 1209600 601
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0