ns4.collisioncode.com has no MX records.
Question and response
Question
dig ns4.collisioncode.com. MX
Answer
The response has no answer records.
Authority
collisioncode.com. 86400 SOA ns1.collisioncode.com. proxystudios.gmail.com. 2026010901 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0