Added troubleshooting for common EPP problems

Author: getpinga

README.md

@@ -77,3 +77,17 @@ Next, head to the "**Registrars**" tab. Here, you'll need to enter your specific
 ## 7. Adding a New TLD:
 
 Finally, add a new Top Level Domain (TLD) using your module from the "**New Top Level Domain**" tab. Make sure to configure all necessary details, such as pricing, within this tab.
+
+# Troubleshooting
+
+If you experience problems connecting to your EPP server, follow these steps:
+
+1. Ensure your server's IP (IPv4 and IPv6) is whitelisted by the EPP server.
+
+2. Confirm your client and server support IPv6 if required. If needed, disable IPv6 support in EPP server.
+
+3. Reload the EPP module or restart the web server after any changes.
+
+4. Ensure certificates have the correct permissions: `chown www-data:www-data cert.pem` and `chown www-data:www-data key.pem`.
+
+5. Verify the EPP module is configured with the chosen registrar prefix.