spf.a2hosting.com has no NS records.
NS records for this zone are defined at a2hosting.com.
NS records for this zone are defined at a2hosting.com.
Question and response
Question
dig spf.a2hosting.com. NS
Answer
The response has no answer records.
Authority
a2hosting.com. 1800 SOA cass.ns.cloudflare.com. dns.cloudflare.com. 2398195270 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0