This problem is happening after I updated Cornerstone to a recent version.
As I am making changes to my page in Cornerstone, I like to frequently save so that I do not lose any changes. This used to work very well before. But now while making changes, when I save, it allows me to save only once. After that I cannot save any more and I have to exit the dashboard and start editing the page again to save changes. So in essence, I can make only one change at a time.
Appreciate your assistance.