Hello,
I may have an amateur problem, but I couldn’t find anything similar in the forum.
I have Theme-X + Cornersone on my site. Updated. It has worked some months ago. The developed site is available on its URL. However, it cannot be edited in Cornerstone. You can see the list of pages, but the page is not visible in the preview, you cannot edit it in any way. The dead Cornerstone page in the pic.
Thank you for help!