dns7071.umbrella.com has no CNAME records.
Question and response
Question
dig dns7071.umbrella.com. NS
Answer
The response has no answer records.
Authority
umbrella.com. 10800 SOA auth1.opendns.com. hostmaster.opendns.com. 1773025049 16384 2048 1048576 2560
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0