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.
For pages, please ensure that this option is already enabled in Rank Math > Titles & Meta > Pages

Here’s a link for more information:
https://rankmath.com/kb/pillar-content-internal-linking/
Hope that helps.
Thank you.
Your answer didn’t help but I went back and found the “pillar content” checkbox on pages. Thx.
Hello,
We’re glad that you managed to resolve this issue.
Please feel free to reach out to us again in case you need any other assistance.
We are here to help.
Thank you.