Can not access tomcat via port 8443 in AWS Singapore when using Singapore IP

I follow this tutorial to install Mifosx with tomcat7 in a debian EC3 in Singapore region

Then I follow this to isntall a free startSSL for my server.

Everything is ok for me in Vietnam (already tried to change IP, change PC... still ok)

But other countries (even my friend in Singapore and a Sing windows VPS) can not access to the VPS through both

htt ps://xxx.xxx.xxx.xxx:8443

and

htt ps://mifos.domain.com:8443.

(with no space between htt and ps) It just stuck at loading.

I've check all the log file under /var/log/* and /var/log/tomcat7/*, everything ok when I access from Vietnam, but nothing even error happen when I try from other countries

Also checked and allow port 8443 in iptables

admin@ip-172-31-1-14:~$ sudo iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
ACCEPT     tcp  --  anywhere             anywhere             tcp     dpt:8443

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination  

this is a server setting:

<?xml version='1.0' encoding='utf-8'?>
<Server port="8005" shutdown="SHUTDOWN">
<Listener className="org.apache.catalina.core.JasperListener" />
<Listener     className="org.apache.catalina.core.JreMemoryLeakPreventionListener" />
<Listener     className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />
<Listener     className="org.apache.catalina.core.ThreadLocalLeakPreventionListener" />

  <GlobalNamingResources>
       <Resource name="UserDatabase" auth="Container"
          type="org.apache.catalina.UserDatabase"
          description="User database that can be updated and saved"
          factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
          pathname="conf/tomcat-users.xml"
       />

       <Resource type="javax.sql.DataSource"
        name="jdbc/mifosplatform-tenants"
        factory="org.apache.tomcat.jdbc.pool.DataSourceFactory"
        driverClassName="com.mysql.jdbc.Driver"
        url="jdbc:mysql://localhost:3306/mifosplatform-tenants"
        username="root"
        password="zxcasdqwe123"
        initialSize="3"
        maxActive="10"
        maxIdle="6"
        minIdle="3"
        validationQuery="SELECT 1"
        testOnBorrow="true"
        testOnReturn="true"
        testWhileIdle="true"
        timeBetweenEvictionRunsMillis="30000"
        minEvictableIdleTimeMillis="60000"
        logAbandoned="true"
        suspectTimeout="60"
       />
  </GlobalNamingResources>
  <Service name="Catalina">
  <Connector protocol="org.apache.coyote.http11.Http11Protocol"
       port="8443" maxThreads="200"
   scheme="https" secure="true"
   SSLEnabled="true" sslProtocol="TLS"
   keystoreFile="/usr/share/mifosx/checkthecrowd.jks"
   keystorePass="zxcasdqwe123"
   clientAuth="false"
       URIEncoding="UTF-8"
   compression="force"
       compressableMimeType="text/html,text/xml,text/plain,text/javascript,text/css"/>
  <Engine name="Catalina" defaultHost="localhost">
      <Realm className="org.apache.catalina.realm.LockOutRealm">
        <Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/>
      </Realm>

     <Host name="localhost"  appBase="webapps" unpackWARs="true" autoDeploy="true">

          <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
               prefix="localhost_access_log." suffix=".log"
               pattern="%h %l %u %t &quot;%r&quot; %s %b" />
     </Host>
    </Engine>
  </Service>
</Server>

some extra stuffs I've tried without luck:

• change to the default self signed certification

• reboot vps

• change Elastic IP

• change hostname and domain

PS: I've an old server which had an mifos and tomcat installed worked well for all country.

Thanks in advanced if you can help me out.