Ninja Firewall is blocking my server’s IP address

The policy is “NinjaFirewall > Firewall Policies > WordPress AJAX > Protect admin-ajax.php against bots”. By default, it is disabled.
Normally, if you enabled that policy, it shouldn’t block your server’s IP address. Maybe your server has multiple IPs? Check below the policy, the IP will be displayed: does it match the blocked IP?

Thanks for your reply.

No, it is showing the IP of the docker container of my website. What to do in this situation?

You’d need to disable the “NinjaFirewall > Firewall Policies > WordPress AJAX > Protect admin-ajax.php against bots” policy. It is disabled by default, and the reason is because many plugins or themes may need to access the admin AJAX API.

I disabled it but is there any workaround to leave it on? Do I need to leave it on when having my website inside a container?

If you want to whitelist that IP so that you can enable that option, you can use the .htninja script.
Here’s an example of code to add to the file, that will whitelist IP 1.2.3.4 :

<?php
/*
 ===========================================================================================+
 | NinjaFirewall optional configuration file                                                                                                                                          
 | See: https://blog.nintechnet.com/ninjafirewall-wp-edition-the-htninja-configuration-file/ 
+===========================================================================================+
*/

if ( $_SERVER["REMOTE_ADDR"] == '1.2.3.4' ) {
   define('NFW_UWL', true);
   return 'ALLOW'; // whitelist
}