asterisk pjsip trunk error

Getting the following error continually in asterisk log, related to qualify_frequency I believe.

[Mar 28 23:17:43] ERROR[4812]: res_pjsip.c:3770 endpt_send_request: Error 320047 'No answer record in the DNS resp
onse (PJLIB_UTIL_EDNSNOANSWERREC)' sending OPTIONS request to endpoint flowroute


[flowroute]
type=auth
auth_type=userpass
password=******
username=******
[flowroute]
type=aor
contact=sip:sip.flowroute.com:5060
qualify_frequency = 15

[flowroute]
type=endpoint
transport=transport-udp
context=from-flowroute
disallow=all
allow=ulaw
outbound_auth=flowroute
aors=flowroute

[flowroute]
type=identify
endpoint=flowroute
match=216.115.69.144
match=70.167.153.130