spf.freshbooks.com has no MX records.
Question and response
Question
dig spf.freshbooks.com. MX
Answer
The response has no answer records.
Authority
freshbooks.com. 60 SOA ns-cloud-c1.googledomains.com. sysadmin.freshbooks.com. 1 21600 3600 259200 60
Additional
. 0 OPT ; payload 512, xrcode 0, version 0, flags 0