mail.spectranet.com has no CNAME records.
Question and response
Question
dig mail.spectranet.com. NS
Answer
The response has no answer records.
Authority
spectranet.com. 3776 SOA ns2.spectranet.com. idcsupport.spectranet.in. 2025013102 28800 7200 86400 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0