Hello,
Thank you for your query and we are so sorry about the trouble this must have caused.
As we explained in the other ticket about the same, you need to follow the steps here to correct the issue: https://rankmath.com/kb/api-http-400-error/
If you are not sure how to whitelist IP addresses you can get in touch with your hosting provider about it.
From our end, it’s not possible to simply whitelist the IP address, otherwise, we would do it and prevent this from happening.
Don’t hesitate to get in touch if you have any other questions.
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.