Hello,
Thank you for contacting Rank Math and bringing your concern to our attention. I’m sorry for any inconvenience this issue may have caused you.
I’ve checked those pages, and it seems that they are empty category pages.
To index them, head over to Rank Math > Titles & Meta > Global Meta and disable this option:

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 the Easy Mode. Please follow the steps in this link to switch to Advanced Mode:
https://rankmath.com/kb/advanced-mode/
I hope that helps.
Thank you, and please don’t hesitate to contact us anytime if you need further assistance with anything else.
Thanks – this seems to have fixed the issue.
Hello,
You’re welcome.
We are super happy that this issue is already resolved. If you have any other questions in the future, know that we are here to help you.
If you don’t mind us 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 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.