mail.glinetele.com has no CNAME records.
Question and response
Question
dig mail.glinetele.com. NS
Answer
The response has no answer records.
Authority
glinetele.com. 10800 SOA ns1.glinetele.com. info.glinetele.com. 2020112504 10800 3600 604800 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0