EC2 - ERR_CONNECTION_TIMED_OUT

I have a ec2 free tier instance running linux, apache web server and nodejs app.

I have configured security group and it worked ok so far.

But now i can not access server through DOMAIN or IP with port (port have opened in inbound rule).

I use ssh to remote server and log pm2 but it work ok. Then I have using lynx to browser localhost in command and nodejs app still running in that port.

Apache log is active (running).

Before I write this post, I cannot connect ssh to server and instance have status StatusCheckFailed_Instance, and I reboot instance, so it worked ok. After that, about 2 hour, I access again and met this problem.

Can anyone suggest what make this problem. Thanks.

UPDATE

After reboot ec2 instance, it works ok, but after 10 minutes cannot connect to server.

I go to log of apache in error_log.

[Sat Aug 22 17:28:34.698537 2020] [mpm_event:notice] [pid 5050:tid 140422190045376] AH00492: caught SIGWINCH, shutting down gracefully
[Sat Aug 22 17:32:05.288561 2020] [suexec:notice] [pid 3666:tid 140585338529984] AH01232: suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Sat Aug 22 17:32:05.314134 2020] [lbmethod_heartbeat:notice] [pid 3666:tid 140585338529984] AH02282: No slotmem from mod_heartmonitor
[Sat Aug 22 17:32:05.316840 2020] [mpm_event:notice] [pid 3666:tid 140585338529984] AH00489: Apache/2.4.43 () OpenSSL/1.0.2k-fips configured -- resuming normal operations
[Sat Aug 22 17:32:05.316866 2020] [core:notice] [pid 3666:tid 140585338529984] AH00094: Command line: '/usr/sbin/httpd -D FOREGROUND'
    

[Sat Aug 22 17:32:05.637067 2020] [proxy:error] [pid 3670:tid 140584547055360] (111)Connection refused: AH00957: HTTP: attempt to connect to 127.0.0.1:6969 (127.0.0.1) failed
[Sat Aug 22 17:32:05.637097 2020] [proxy_http:error] [pid 3670:tid 140584547055360] [client *****:****] AH01114: HTTP: failed to make connection to backend: 127.0.0.1, referer: https://***.herokuapp.com/profile

At 17:32 I access ip ok. After 10 minutes it down. But in log file it error even in 17:32.

This is my apache config.

<VirtualHost *:80>    
     ServerAdmin **@gmail.com    
     DocumentRoot /var/www/html/hhs_api    
     ServerName api.***.xyz    
     Redirect / https://api.***.xyz/
    <Directory "/var/www/html/hhs_api">
         Order deny,allow
         Allow from all
         AllowOverride All
         Require all granted
   </Directory>    
<Location />
</Location>    
</VirtualHost>

This is ssl config

<VirtualHost _default_:443>
    SSLEngine On
    SSLProxyEngine On
    ProxyRequests Off
    ProxyPreserveHost On
    SSLProxyVerify none
    SSLProxyCheckPeerCN off
    SSLProxyCheckPeerName off
    SSLProxyCheckPeerExpire off
    ServerAdmin ***@gmail.com
    DocumentRoot /var/www/html/hhs_api
    ServerName api.***.xyz
    SSLCertificateFile "/etc/httpd/conf/hhs_api-ssl/certificate.crt"
    SSLCertificateChainFile "/etc/httpd/conf/hhs_api-ssl/ca_bundle.crt"
    SSLCertificateKeyFile "/etc/httpd/conf/hhs_api-ssl/private.key"

        ProxyPass /  http://127.0.0.1:6969/
        ProxyPassReverse / http://127.0.0.1:6969/

    <Directory "/var/www/html/hhs_api">
         Order deny,allow
         Allow from all
         AllowOverride All
         Require all granted
   </Directory>
</VirtualHost>

Before today, everything work ok. I dont know why.