Hello,
Thanks for contacting us, and sorry for any inconvenience that might have been caused due to that.
The notice should be cleared once you just click the x button on the notification.
If it’s still not getting removed, clear your website’s cache and the transients at Rank Math > Status & Tools > Database Tools > Remove transients.

Please note that some options are only available when you enable the Advanced Mode in Rank Math. If it’s not showing, you must have chosen to use Easy Mode. Please follow the steps in this link to switch to Advanced Mode:
https://rankmath.com/kb/advanced-mode/
Let us know how this goes. Looking forward to helping you.
Thank you.
Thanks, I clicked 2 more times and removed transients and it disappeared.
Hello,
We are super happy that this resolved your issue. 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.