403 Forbidden error code is shown when your server permissions don’t allow access to a specific page.

What Causes 403 Forbidden Error in WordPress?

The most common cause for the 403 Forbidden error in WordPress is due to poorly configured security plugins. Many WordPress security plugins can block an IP address (or a whole range of IP addresses) if they believe them to be malicious.

Another possible cause could be a corrupt .htaccess file or incorrect file permissions on your server.

Your WordPress hosting company can sometimes make accidental changes to its server settings. This may result in a 403 Forbidden error on your site.

How to Fix the 403 Forbidden Error in WordPress?

• Disable ALL of your plugins aside from the BuddyBoss Platform.  If the step above solves the issue, activate your plugins one at a time, checking your website each time a plugin is activated.
• If you have identified that a third-party plugin, not listed on our integrations page, is causing the issue, reach out to the plugin support for assistance. 
• Reach out to your hosting/server provider so they can check the issue on their end. 

You can check this related article to learn more:
https://www.wpbeginner.com/wp-tutorials/how-to-fix-the-403-forbidden-error-in-wordpress/