Hello,
Thank you for contacting Rank Math support, and sorry for any inconvenience that might have been caused due to that.
If you have already followed the guide and whitelisted our IP and user agent please clear the SEO Analysis cache by going to Rank Math > Status & Tools > Database Tools > Clear SEO Analysis:

Once done, clear your website cache and re-run the SEO Analysis.
If the issue persists, let us know and we will help you further troubleshoot the issue.
Looking forward to helping you.
Hi,
I did both but the issue remains.
Hello,
If the SEO Analysis is still returning a 400 error, it means that it is still getting blocked. Please make sure that you have whitelisted the IP and user agent mentioned in the guide: https://rankmath.com/kb/api-http-400-error/
If you are using a firewall or Cloudflare, make sure that you whitelist the IP and user agent there too.
Let us know how that goes. Looking 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.