Hello,
Thank you for contacting Rank Math, and sorry for any inconvenience caused.
The 400 status code indicates that the server was unable to process the request sent.
However, as an initial troubleshooting step, we’ve seen a case in the past where this was related to compatibility between the W3 Total Cache plugin and the hosting. Here’s the thread link: https://support.rankmath.com/ticket/instant-indexing-error-undefined-4/
Could you confirm if you’re using the W3 Total Cache plugin? If yes, please try temporarily disabling it and see if it helps.
In any case, please ensure that the admin area of the website is not getting cached by any caching plugin on the website or the server.
You can also get in touch with your web host regarding this and see if they have further insights into the error.
Looking forward to hearing back from you.
Thank you.
Dear Team!
Thank you for replying to me. actually, after few hours I just came back to double check and re-connect again, and that problem was automatically solved out. It was success for connection. I thought that was from Rank Math team.
I noted your tip about W3 tool cache plugin (yes, I’ve use it for my website)
By the way, thank again for support to me.
Hello,
We are glad we could address your concern. If you have any other questions in the future, know that we are here to help you.
If you don’t mind me asking, could you please leave us a review (if you haven’t already) on https://wordpress.org/support/plugin/seo-by-rank-math/reviews/#new-post about your overall experience with Rank Math? We appreciate your time and patience.
If you do have another question in the future, please feel free to create a new forum topic, and it will be our pleasure to assist you again.
Thank you.
