_spf.les.net has no MX records.
Question and response
Question
dig _spf.les.net. MX
Answer
The response has no answer records.
Authority
les.net. 300 SOA ns1.les.net. arin.les.net. 1390 60 60 7257600 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0