mx.rima-tde.net has no CNAME records.
Question and response
Question
dig mx.rima-tde.net. NS
Answer
The response has no answer records.
Authority
rima-tde.net. 10800 SOA kairos.rima-tde.net. residencial.rima-tde.net. 2024112641 28800 7200 259200 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0