mx3.casjaysdev.pro has no CNAME records.
Question and response
Question
dig mx3.casjaysdev.pro. NS
Answer
The response has no answer records.
Authority
casjaysdev.pro. 3884 SOA dns.casjaysdev.pro. dns-admin.casjaysdev.pro. 2026010370 10800 3600 1209600 38400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0