nps2.domainkey.u3789899.wl150.sendgrid.net has no NS records.
NS records for this zone are defined at wl150.sendgrid.net.
NS records for this zone are defined at wl150.sendgrid.net.
Question and response
Question
dig nps2.domainkey.u3789899.wl150.sendgrid.net. NS
Answer
The response has no answer records.
Authority
wl150.sendgrid.net. 1800 SOA aisha.ns.cloudflare.com. dns.cloudflare.com. 2399744451 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0