mx.tigo.com.py has no CNAME records.
Question and response
Question
dig mx.tigo.com.py. NS
Answer
The response has no answer records.
Authority
tigo.com.py. 3379 SOA inet2.telecel.com.py. networksupport.tigo.net.py. 2023071937 1800 600 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0