nashua.skillsoft.com has no CNAME records.
Question and response
Question
dig nashua.skillsoft.com. NS
Answer
The response has no answer records.
Authority
skillsoft.com. 8970 SOA udns1.cscdns.net. hostmaster.cscdns.net. 7462 86400 86400 86400 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0