Hello,
Thank you for contacting Rank Math, and sorry for any inconvenience caused.
Please check the individual post/page settings by going to the post/page > SEO Settings > Advanced Tab > Check index checkbox > Save
Do note that some options are only available when you enable the Advanced Mode in the Rank Math dashboard:

If the individual post is set to index and the issue persists, please share the affected URL in the sensitive data section.
We look forward to helping 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.