Error Sorry, you are not allowed to access this page

Hi,

I’m facing exactly the same problem as mentioned here:
https://www.ads-software.com/support/topic/unable-to-access-settings-page-of-webstories/

My site is hosted on WPEngine. All plugins are working fine as expected.

Just installed Google Web Stories but after activating page, the Web Stories menu link does not appear on left hand side column.

And when we go to settings page:
https://rollingstoneindia.com/wp-admin/edit.php?post_type=web-story&page=stories-dashboard#/editor-settings

it gives error:
Sorry, you are not allowed to access this page.

Plugin version is: 1.21.1

p.s.: i’ve another site with version 1.20.0 which is working fine.

The page I need help with: [log in to see the link]