ptr.cidc.telus.com has no MX records.
Question and response
Question
dig ptr.cidc.telus.com. MX
Answer
The response has no answer records.
Authority
ptr.cidc.telus.com. 86400 SOA dns1.cidc.telus.com. support.cidc.telus.com. 2025080600 28800 7200 604800 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0