Saving gives me a 404 error.

Hello,

Thanks for contacting us and sorry for any inconvenience that might have been caused due to that.

Please check your browser console for script errors when you save the settings in Rank Math.

You can share a screenshot of the error using a tool like https://imgur.com/

Looking forward to helping you.

Hello,

We might need to take a closer look at the settings. Please edit the first post on this ticket and include your WordPress logins in the designated Sensitive Data section.

Please do take a complete backup of your website before sharing the information with us.

It is completely secure and only our support staff has access to that section. If you want, you can use the below plugin to generate a temporary login URL to your website and share that with us instead:

https://wordpress.org/plugins/temporary-login-without-password/

You can use the above plugin in conjunction with the WP Security Audit Log to monitor what changes our staff might make on your website (if any):

https://wordpress.org/plugins/wp-security-audit-log/

We really look forward to helping you.