coho.telusmobility.com has no CNAME records.
Question and response
Question
dig coho.telusmobility.com. NS
Answer
The response has no answer records.
Authority
telusmobility.com. 300 SOA dns8.telus.com. dnsadmin2.telus.com. 2021052771 900 7200 3600000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0