mx.uceprotect.net has no CNAME records.
Question and response
Question
dig mx.uceprotect.net. NS
Answer
The response has no answer records.
Authority
uceprotect.net. 1785 SOA guss.ns.cloudflare.com. dns.cloudflare.com. 2397207397 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0