forgot to save form

To clarify, are you editing the form and you have forgotten to save it or are your referring to save the form user's ability to save their form progression?

Do note that when you edit your form in the form builder it will auto save any changes you have made.

You may enable the continue form later feature to let your form respondents save their progress and get back to submit the form.

To enable this feature, go to your Settings>Form Settings>Continue Forms Later and set it to Enabled.

However, if you're referring to something else, kindly share more information regarding the issue with your form.