ns4.omnispring.com has no CNAME records.
Question and response
Question
dig ns4.omnispring.com. NS
Answer
The response has no answer records.
Authority
omnispring.com. 1730 SOA ns1.omnispring.com. dnsmanager.omnispring.com. 2026022300 3600 600 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0