Your ntpq -pn output indicates that ntpd is trying to query the *.asia.pool.ntp.org servers, but failing to get any response at all. Only the local clock has been used successfully.
The problem is that your iptables ruleset is stopping the incoming NTP protocol messages. The ordering of iptables rules is very important: in your ruleset, the rule for allowing NTP traffic (UDP port 123) has the right syntax, but it is after a rule that rejects all traffic that has not been accepted by a previous rule. So your NTP rule will never be effective in that location.
To fix it, move the "accept NTP" rule before the "reject everything (that has not already been accepted)" rule:
[...] -A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 6000:6010 -j ACCEPT -A RH-Firewall-1-INPUT -m state --state NEW -m udp -p udp --dport 123 -j ACCEPT -A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited COMMIT
