mail3.hostpro.ua has no CNAME records.
Question and response
Question
dig mail3.hostpro.ua. NS
Answer
The response has no answer records.
Authority
hostpro.ua. 1800 SOA kallie.ns.cloudflare.com. dns.cloudflare.com. 2397448575 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0