mx.flextovia.com has no NS records.
NS records for this zone are defined at flextovia.com.
NS records for this zone are defined at flextovia.com.
Question and response
Question
dig mx.flextovia.com. NS
Answer
The response has no answer records.
Authority
flextovia.com. 3600 SOA dns.flextovia.com. hostmaster.flextovia.com. 1799727845 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0