I am not sure but it seems to be related to the limit on free hosting:
100 CMS items, and 50 form submissions
I do not have 100 items but I have deleted and re created a lot of pages. My guess here is that I have created 100 pages but the deleted ones are being counted.
To test this I cloned the site and it works fine on the new cloned copy. I can add more pages
My solution was to rename my project then clone it with the original name.
Hello @andyjames Sorry about the collection item limit issue. Can you send an email to support@webflow.com ? We’ll take a look at the issue right away.
If there are multiple collections, and each collection has a few items, all items in all collections count toward the cms hosting limit of 100 items on the free plan.
Once the hosting subscription is added, the 100 limit will be removed.