mail.mivocloud.com has no NS records.
NS records for this zone are defined at mivocloud.com.
NS records for this zone are defined at mivocloud.com.
Question and response
Question
dig mail.mivocloud.com. NS
Answer
The response has no answer records.
Authority
mivocloud.com. 1800 SOA jeremy.ns.cloudflare.com. dns.cloudflare.com. 2398573072 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0