spf.servicenowservices.com has no NS records.
NS records for this zone are defined at servicenowservices.com.
NS records for this zone are defined at servicenowservices.com.
Question and response
Question
dig spf.servicenowservices.com. NS
Answer
The response has no answer records.
Authority
servicenowservices.com. 60 SOA use1.akam.net. root.service-now.com. 594663 900 1800 31536000 60
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0