terrystevens

The response from RankMath support is

“We checked if the metadata was saving in the learning mode and if the routes were allowed correctly in the firewall or not. However, since the issue is coming because WordFence is not applying the same settings as the admin role to the author role, they will be in a better position to check this further.”

I can deal with slow refresh but Nested Pages isnt displaying for me at all.

I also have over 2000 pages

Yep that seems to have done the trick.
Looks to be working fine now.

Thanks for such a prompt response!