pool.ntp.casjaydns.com has no AAAA records.
Question and response
Question
dig pool.ntp.casjaydns.com. AAAA
Answer
pool.ntp.casjaydns.com. 5 CNAME casjay.pool.ntp.org.
Authority
pool.ntp.org. 1300 SOA i.ntpns.org. hostmaster.pool.ntp.org. 1772050326 5400 5400 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0