mail7.ee-docs.com has no NS records.
NS records for this zone are defined at ee-docs.com.
NS records for this zone are defined at ee-docs.com.
Question and response
Question
dig mail7.ee-docs.com. NS
Answer
The response has no answer records.
Authority
ee-docs.com. 3600 SOA dns1.amx.com.pe. hostmaster.ee-docs.com. 2017033753 5400 600 90000 7200
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0