_spf.belledonne-communications.com has no MX records.
Question and response
Question
dig _spf.belledonne-communications.com. MX
Answer
The response has no answer records.
Authority
belledonne-communications.com. 10800 SOA ns1.gandi.net. hostmaster.gandi.net. 1772064000 10800 3600 604800 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0