mx.valflowers.com has no NS records.
NS records for this zone are defined at valflowers.com.
NS records for this zone are defined at valflowers.com.
Question and response
Question
dig mx.valflowers.com. NS
Answer
The response has no answer records.
Authority
valflowers.com. 3600 SOA dns.valflowers.com. hostmaster.valflowers.com. 1559919069 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0