Hello,
Thank you for contacting Rank Math support, and sorry for any inconvenience that might have been caused due to that.
I checked the affected pages you shared and they are already set to index in their robots meta tag. Please clear your website cache and allow Google to recrawl the pages.
One thing to check here is that I noticed there’s a script that seems to be coded to programmatically set the robots tag to noindex. Please check my screenshot of your page source:

Can you please confirm this? This could be added from another plugin on your website.
Looking forward to helping you on this one.
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.