Hello,
Thank you for contacting Rank Math, and sorry for any inconvenience caused.
5xx errors are usually caused due to server misconfiguration or other server issues.
Can you please share the website error log with us?
Having the error log file will give a clear idea of why this might be happening.
You can follow this guide to enable debugging in WordPress
https://wordpress.org/support/article/debugging-in-wordpress/ or you can get in touch with your web host, they will help you locate the log file.
You can also check if any plugin or theme is conflicting with Rank Math.
To determine that, please follow this guide:
https://rankmath.com/kb/check-plugin-conflicts/
Looking forward to helping you.
1. I tried https://wordpress.org/support/article/debugging-in-wordpress/ enabling the log file but I’m not getting any error message relating to the 500 error.
Here is the 500 error in the console.
Request URL: http:/… .com/wp-json/rankmath/v1/in/submitUrls
Request Method: POST
Status Code: 500 Internal Server Error
Remote Address: 39.106.49.148:80
Referrer Policy: strict-origin-when-cross-origin
Could you please offer some advise on how to troubleshoot this API (v1/in/submitUrls)? I can read PHP code.
2. Also tried https://rankmath.com/kb/check-plugin-conflicts/ Amd only enable the RankMath plugin, but still getting the exact same error, and error code 0
What else am I missing here? Please advise.
Best,
Hello,
We might need to take a closer look at the settings. Please edit the first post on this ticket and include your WordPress & FTP 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.
Hello,
Since we did not hear back from you for 15 days, we are assuming that you found the solution. We are closing this support ticket.
If you still need assistance or any other help, please feel free to open a new support ticket, and we will be more than happy to assist.
Thank you.