mail.invest-it.com.ua has no NS records.
NS records for this zone are defined at invest-it.com.ua.
NS records for this zone are defined at invest-it.com.ua.
Question and response
Question
dig mail.invest-it.com.ua. NS
Answer
The response has no answer records.
Authority
invest-it.com.ua. 1800 SOA lina.ns.cloudflare.com. dns.cloudflare.com. 2397886087 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0