spf.mindbox.ru has no NS records.
NS records for this zone are defined at mindbox.ru.
NS records for this zone are defined at mindbox.ru.
Question and response
Question
dig spf.mindbox.ru. NS
Answer
The response has no answer records.
Authority
mindbox.ru. 300 SOA ns1.edgedns.co. support.edgecenter.ru. 1772143493 5400 3600 1209600 300
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0