mxsmtp.wimaxtigo.bo has no CNAME records.
Question and response
Question
dig mxsmtp.wimaxtigo.bo. NS
Answer
The response has no answer records.
Authority
wimaxtigo.bo. 10800 SOA ns1.wimaxtigo.bo. hostmaster.wimaxtigo.bo. 2018082713 10800 900 1814400 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0