spf.managedns.org has no TXT records.
Question and response
Question
dig spf.managedns.org. TXT
Answer
The response has no answer records.
Authority
managedns.org. 3600 SOA dns16.managedns.org. hostmaster.managedns.org. 2014015042 3600 600 1209600 3600
Additional
. 0 OPT ; payload 4000, xrcode 0, version 0, flags 0