Hello,
Thank you for contacting Rank Math and sorry for any inconvenience that might have been caused due to that.
The first thing we need to do is solve the 404 error so we can then tackle the critical error. To fix this we recommend following this guide: https://rankmath.com/kb/sitemap-404-error/
After that, please make sure that you enable the WordPress debugging and access the sitemap that is throwing the critical error.
Then share the error message that populated in the debug log for WordPress which will include more information on where exactly is the error so we can advise further.
Looking forward to hearing back from 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.
