If i create a new form, the first time when i save the form, its possible to add a list. But if i refresh the page, or switch to the repsonse email, my changes will not be saved again. In your code you have an JS error, when you are in in the edit mode of a form.
Maybe this helps.
Uncaught TypeError: Cannot read property ‘replace’ of undefined: shortcodes.js?ver=1:238
Uncaught TypeError: Cannot read property ‘replace’ of undefined: form-cpt.js?ver=1:89