Session Information Not Retained

I have developed the fields/calculations on a WooCommerce Product page. After the user makes their entries in the field they add it to their cart. If a user forgets to fill in a field, they need the ability to have the information retain when they go back to edit the Product fields. Right now, the filled in information is gone when the user attempts to go back to the product fields. This is a huge problem.

How can this be fixed?

There are no error codes in the browser Console.
I already changed to a WordPress default theme to see if it’s caused by a theme conflict: same problem.
I have no caching plugins running or any other systematic plugins.
I’d give you the page, but it’s private.